DBPedias

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Michelle Ufford

  1. BCP Script Generator

    I'm currently working on the logic migration of data marts from SQL Server to Teradata. While another team is working on the actual table migration, it's still helpful to have some data in the tables for developing against. The easiest method I've found to do this is to use BCP to export some sample data. So of course, I've created a SQL script that will generate the BCP code for me. Because that's what I like to do on Sunday evenings.

    -- User-defined variables --
     
    DECLARE @tableToBCP NVARCHAR(128)   = 'AdventureWorksDW2008R2.dbo.DimCustomer'
        , @Top          VARCHAR(10)     = NULL -- Leave NULL for all rows
        , @Delimiter    VARCHAR(4)      = '|'
        , @UseNULL      BIT             = 1
        , @OverrideChar CHAR(1)         = '~'
        , @MaxDop       CHAR(1)         = '1'
        , @Directory    VARCHAR(256)    = 'C:\bcp_output\';
     
     
    -- Script-defined variables -- 
     
    DECLARE @columnList TABLE (columnID INT);
     
    DECLARE @bcpStatement NVARCHAR(MAX) = 'BCP "SELECT '
        , @currentID INT
        , @firstID INT;
     
    INSERT INTO @columnList
    SELECT column_id 
    FROM sys.columns 
    WHERE object_id = OBJECT_ID(@tableToBCP)
    ORDER BY column_id;
     
    IF @Top IS NOT NULL
        SET @bcpStatement = @bcpStatement + 'TOP (' + @Top + ') ';
     
    SELECT @firstID = MIN(columnID) FROM @columnList;
     
    WHILE EXISTS(SELECT * FROM @columnList)
    BEGIN
     
        SELECT @currentID = MIN(columnID) FROM @columnList;
     
        IF @currentID <> @firstID
            SET @bcpStatement = @bcpStatement + ',';
     
        SELECT @bcpStatement = @bcpStatement + name
        FROM sys.columns 
        WHERE object_id = OBJECT_ID(@tableToBCP)
            AND column_id = @currentID;
     
        DELETE FROM @columnList WHERE columnID = @currentID;
     
     
    END;
     
    SET @bcpStatement = @bcpStatement + ' FROM ' + @tableToBCP 
        + ' WITH (NOLOCK) OPTION (MAXDOP 1);" queryOut '
        + @Directory + REPLACE(@tableToBCP, '.', '_') + '.dat -S' + @@SERVERNAME
        + ' -T -t"' + @Delimiter + '" -c -C;'
     
    SELECT @bcpStatement;

    This will generate a standard BCP script:

    BCP "SELECT CustomerKey,GeographyKey,CustomerAlternateKey,Title,FirstName,MiddleName,
    LastName,NameStyle,BirthDate,MaritalStatus,Suffix,Gender,EmailAddress,YearlyIncome,
    TotalChildren,NumberChildrenAtHome,EnglishEducation,SpanishEducation,FrenchEducation,
    EnglishOccupation,SpanishOccupation,FrenchOccupation,HouseOwnerFlag,NumberCarsOwned,
    AddressLine1,AddressLine2,Phone,DateFirstPurchase,CommuteDistance 
    FROM AdventureWorksDW2008R2.dbo.DimCustomer WITH (NOLOCK) OPTION (MAXDOP 1);" queryOut 
    C:\bcp_output\AdventureWorksDW2008R2_dbo_DimCustomer.dat -SSQLFOOL -T -t"|" -c -C;

    However, I've been running into some issues with the data load. See, the thing... I'm finding that some of my tables don't... that is to say... they may possibly contain... [whisper]uncleansed data[/whisper]. I know, I know... this may come as a shock to many of you, and all I ask is that you please don't judge me for it. ;)

    What do I mean by "uncleansed data?" I mostly mean user-inputted VARCHAR columns that contain pipes (|), tabs, carriage returns, and line feeds. These types of characters tend to mess with the data import process. Also, I've not yet found a way to import a data file into Teradata where a non-nullable character column contains an empty string (''). Obviously, the vast majority of the data is fine, but even one of these issues can throw an error during the import process. I've modified the script above to handle these specific exceptions.

    Since I'm only using this data for testing purposes, I found it pretty easy to simply replace the offending records with ~. I'm not sure if anyone else has a need for this particular script, but I figured you could modify it pretty easily to do whatever you need.

    -- User-defined variables --
     
    DECLARE @tableToBCP NVARCHAR(128)   = 'AdventureWorksDW2008R2.dbo.DimCustomer'
        , @Top          VARCHAR(10)     = NULL -- Leave NULL for all rows
        , @Delimiter    VARCHAR(4)      = '|'
        , @UseNULL      BIT             = 1
        , @OverrideChar CHAR(1)         = '~'
        , @MaxDop       CHAR(1)         = '1'
        , @Directory    VARCHAR(256)    = 'C:\bcp_output\';
     
     
    -- Script-defined variables -- 
     
    DECLARE @columnList TABLE (columnID INT);
     
    DECLARE @bcpStatement NVARCHAR(MAX) = 'BCP "SELECT '
        , @currentID INT
        , @firstID INT;
     
    INSERT INTO @columnList
    SELECT column_id 
    FROM sys.columns 
    WHERE object_id = OBJECT_ID(@tableToBCP)
    ORDER BY column_id;
     
    IF @Top IS NOT NULL
        SET @bcpStatement = @bcpStatement + 'TOP (' + @Top + ') ';
     
    SELECT @firstID = MIN(columnID) FROM @columnList;
     
    WHILE EXISTS(SELECT * FROM @columnList)
    BEGIN
     
        SELECT @currentID = MIN(columnID) FROM @columnList;
     
        IF @currentID <> @firstID
            SET @bcpStatement = @bcpStatement + ',';
     
        SELECT @bcpStatement = @bcpStatement + 
                                CASE 
                                    WHEN user_type_id IN (231, 167, 175, 239) 
                                    THEN 'CASE WHEN ' + name + ' = '''' THEN ' 
                                        + CASE 
                                            WHEN is_nullable = 1 THEN 'NULL' 
                                            ELSE '''' + REPLICATE(@OverrideChar, max_length) + ''''
                                          END
                                        + ' WHEN ' + name + ' LIKE ''%' + @Delimiter + '%'''
                                            + ' OR ' + name + ' LIKE ''%'' + CHAR(9) + ''%''' -- tab
                                            + ' OR ' + name + ' LIKE ''%'' + CHAR(10) + ''%''' -- line feed
                                            + ' OR ' + name + ' LIKE ''%'' + CHAR(13) + ''%''' -- carriage return
                                            + ' THEN ' 
                                            + CASE 
                                                WHEN is_nullable = 1 THEN 'NULL' 
                                                ELSE '''' + REPLICATE(@OverrideChar, max_length) + ''''
                                              END
                                        + ' ELSE ' + name + ' END' 
                                    ELSE name 
                                END 
        FROM sys.columns 
        WHERE object_id = OBJECT_ID(@tableToBCP)
            AND column_id = @currentID;
     
        DELETE FROM @columnList WHERE columnID = @currentID;
     
     
    END;
     
    SET @bcpStatement = @bcpStatement + ' FROM ' + @tableToBCP 
        + ' WITH (NOLOCK) OPTION (MAXDOP 1);" queryOut '
        + @Directory + REPLACE(@tableToBCP, '.', '_') + '.dat -S' + @@SERVERNAME
        + ' -T -t"' + @Delimiter + '" -c -C;'
     
    SELECT @bcpStatement;

    The sample output of this would look like:

    BCP "SELECT CustomerKey,GeographyKey,CASE WHEN CustomerAlternateKey = '' THEN 
    '~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~' WHEN CustomerAlternateKey LIKE '%|%' OR 
    CustomerAlternateKey LIKE '%' + CHAR(9) + '%' OR CustomerAlternateKey LIKE 
    '%' + CHAR(10) + '%' OR CustomerAlternateKey LIKE '%' + CHAR(13) + '%' 
    THEN '~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~' ELSE CustomerAlternateKey END,
    CASE WHEN Title = '' THEN NULL WHEN Title LIKE '%|%' OR Title LIKE '%' + CHAR(9)
     + '%' OR Title LIKE '%' + CHAR(10) + '%' OR Title LIKE '%' + CHAR(13) + '%' 
    THEN NULL ELSE Title END,CASE WHEN FirstName = '' THEN NULL WHEN FirstName 
    LIKE '%|%' OR FirstName LIKE '%' + CHAR(9) + '%' OR FirstName LIKE '%' + 
    CHAR(10) + '%' OR FirstName LIKE '%' + CHAR(13) + '%' THEN NULL ELSE 
    FirstName END,CASE WHEN MiddleName = '' THEN NULL WHEN MiddleName LIKE '%|%'
     OR MiddleName LIKE '%' + CHAR(9) + '%' OR MiddleName LIKE '%' + CHAR(10) +
     '%' OR MiddleName LIKE '%' + CHAR(13) + '%' THEN NULL ELSE MiddleName END,
    CASE WHEN LastName = '' THEN NULL WHEN LastName LIKE '%|%' OR LastName LIKE
     '%' + CHAR(9) + '%' OR LastName LIKE '%' + CHAR(10) + '%' OR LastName LIKE
     '%' + CHAR(13) + '%' THEN NULL ELSE LastName END,NameStyle,BirthDate,CASE 
    WHEN MaritalStatus = '' THEN NULL WHEN MaritalStatus LIKE '%|%' OR 
    MaritalStatus LIKE '%' + CHAR(9) + '%' OR MaritalStatus LIKE '%' + CHAR(10) 
    + '%' OR MaritalStatus LIKE '%' + CHAR(13) + '%' THEN NULL ELSE MaritalStatus 
    END,CASE WHEN Suffix = '' THEN NULL WHEN Suffix LIKE '%|%' OR Suffix LIKE '%' 
    + CHAR(9) + '%' OR Suffix LIKE '%' + CHAR(10) + '%' OR Suffix LIKE '%' + 
    CHAR(13) + '%' THEN NULL ELSE Suffix END,CASE WHEN Gender = '' THEN NULL 
    WHEN Gender LIKE '%|%' OR Gender LIKE '%' + CHAR(9) + '%' OR Gender LIKE '%' 
    + CHAR(10) + '%' OR Gender LIKE '%' + CHAR(13) + '%' THEN NULL ELSE Gender 
    END,CASE WHEN EmailAddress = '' THEN NULL WHEN EmailAddress LIKE '%|%' OR 
    EmailAddress LIKE '%' + CHAR(9) + '%' OR EmailAddress LIKE '%' + CHAR(10) + 
    '%' OR EmailAddress LIKE '%' + CHAR(13) + '%' THEN NULL ELSE EmailAddress END,
    YearlyIncome,TotalChildren,NumberChildrenAtHome, CASE WHEN EnglishEducation = '' 
    THEN NULL WHEN EnglishEducation LIKE '%|%' OR 
    EnglishEducation LIKE '%' + CHAR(9) + '%' OR EnglishEducation LIKE '%' + 
    CHAR(10) + '%' OR EnglishEducation LIKE '%' 
    + CHAR(13) + '%' THEN NULL ELSE EnglishEducation END,CASE WHEN 
    SpanishEducation = '' THEN NULL WHEN SpanishEducation LIKE '%|%' OR 
    SpanishEducation LIKE '%' + CHAR(9) + '%' OR SpanishEducation LIKE '%' + 
    CHAR(10) + '%' OR SpanishEducation LIKE '%' + CHAR(13) + '%' THEN NULL 
    ELSE SpanishEducation END,CASE WHEN FrenchEducation = '' THEN NULL WHEN 
    FrenchEducation LIKE '%|%' OR FrenchEducation LIKE '%' + CHAR(9) + '%' 
    OR FrenchEducation LIKE '%' + CHAR(10) + '%' OR FrenchEducation LIKE '%' 
    + CHAR(13) + '%' THEN NULL ELSE FrenchEducation END,CASE WHEN 
    EnglishOccupation = '' THEN NULL WHEN EnglishOccupation LIKE '%|%' OR 
    EnglishOccupation LIKE '%' + CHAR(9) + '%' OR EnglishOccupation LIKE '%' 
    + CHAR(10) + '%' OR EnglishOccupation LIKE '%' + CHAR(13) + '%' THEN 
    NULL ELSE EnglishOccupation END,CASE WHEN SpanishOccupation = '' THEN 
    NULL WHEN SpanishOccupation LIKE '%|%' OR SpanishOccupation LIKE '%' 
    + CHAR(9) + '%' OR SpanishOccupation LIKE '%' + CHAR(10) + '%' OR 
    SpanishOccupation LIKE '%' + CHAR(13) + '%' THEN NULL ELSE SpanishOccupation 
    END,CASE WHEN FrenchOccupation = '' THEN NULL WHEN FrenchOccupation LIKE 
    '%|%' OR FrenchOccupation LIKE '%' + CHAR(9) + '%' OR FrenchOccupation 
    LIKE '%' + CHAR(10) + '%' OR FrenchOccupation LIKE '%' + CHAR(13) + '%' 
    THEN NULL ELSE FrenchOccupation END,CASE WHEN HouseOwnerFlag = '' THEN 
    NULL WHEN HouseOwnerFlag LIKE '%|%' OR HouseOwnerFlag LIKE '%' + CHAR(9) 
    + '%' OR HouseOwnerFlag LIKE '%' + CHAR(10) + '%' OR HouseOwnerFlag LIKE 
    '%' + CHAR(13) + '%' THEN NULL ELSE HouseOwnerFlag END,NumberCarsOwned,CASE 
    WHEN AddressLine1 = '' THEN NULL WHEN AddressLine1 LIKE '%|%' OR AddressLine1 
    LIKE '%' + CHAR(9) + '%' OR AddressLine1 LIKE '%' + CHAR(10) + '%' OR 
    AddressLine1 LIKE '%' + CHAR(13) + '%' THEN NULL ELSE AddressLine1 END,CASE 
    WHEN AddressLine2 = '' THEN NULL WHEN AddressLine2 LIKE '%|%' OR AddressLine2 
    LIKE '%' + CHAR(9) + '%' OR AddressLine2 LIKE '%' + CHAR(10) + '%' OR 
    AddressLine2 LIKE '%' + CHAR(13) + '%' THEN NULL ELSE AddressLine2 END,CASE 
    WHEN Phone = '' THEN NULL WHEN Phone LIKE '%|%' OR Phone LIKE '%' + CHAR(9) 
    + '%' OR Phone LIKE '%' + CHAR(10) + '%' OR Phone LIKE '%' + CHAR(13) + '%' 
    THEN NULL ELSE Phone END,DateFirstPurchase,CASE WHEN CommuteDistance = '' 
    THEN NULL WHEN CommuteDistance LIKE '%|%' OR CommuteDistance LIKE '%' + 
    CHAR(9) + '%' OR CommuteDistance LIKE '%' + CHAR(10) + '%' OR CommuteDistance 
    LIKE '%' + CHAR(13) + '%' THEN NULL ELSE CommuteDistance END 
    FROM AdventureWorksDW2008R2.dbo.DimCustomer WITH (NOLOCK) OPTION (MAXDOP 1);" queryOut 
    C:\bcp_output\AdventureWorksDW2008R2_dbo_DimCustomer.dat -SSQLFOOL -T -t"|" -c -C;

    I don't know about you, but that would take me a bit longer to write manually than to execute the script above. :)

    One note: I've found that copying this code into a batch file will actually render the CHAR functions, i.e. CHAR(13) will be replaced with a carriage return in the script. To avoid this, copy and paste the BCP script directly into your command window.

    Not familiar with BCP? Refer to my blog post on BCP Basics to help get you started.

  2. Are You Approaching Your Partition Range Limits?

    In my post last week, How To Estimate Data Utilization, I said that it may be my last post for a while. Well... apparently I lied. :)

    For those of you who use table partitioning, you know that you need to define a partitioning scheme and function prior to applying partitioning to an index. Personally, I tend to build the function for a couple of years out, and I tend to create them through the end of a calendar year. Now, if I failed to expand a partition range at the end of the year, then come January 1st, all of my data would be written to the same partition. Not the end of the world, no, but it causes all kinds of nasty performance and maintenance issues. Thus, as part of my end-of-year / maternity-leave preparations, I'm in the process of examining all partitioned functions to identify those that need to have their partition ranges expanded. For those interested, here's the script I used:

    IF OBJECT_ID('tempdb..#Results') IS NOT NULL
        DROP TABLE #Results;
     
    CREATE TABLE #Results
    (
          databaseName  NVARCHAR(128)
        , schemaName    NVARCHAR(128)
        , functionName  NVARCHAR(128)
        , data_space_id INT
        , maxRangeValue SQL_VARIANT
    )
     
    /* Grab results for each database and store in our temp table.  
       And no, I don't *need* to select from sys.indexes and perform 
       left joins, but I'm overly cautious and want to make sure 
       I'm not accidentally missing any databases. :) */
     
    --EXECUTE master.dbo.sp_msforeachdb
    EXECUTE sp_foreachdb 'USE ?;
    INSERT INTO #Results
    SELECT DB_NAME() AS databaseName
        , sps.name AS schemaName
        , spf.name AS functionName
        , sps.data_space_id 
        , MAX(prv.value) AS maxRangeValue
    FROM sys.indexes AS i
    LEFT JOIN sys.partition_schemes AS sps WITH (NOLOCK)
        ON i.data_space_id = sps.data_space_id
    LEFT JOIN sys.partition_functions AS spf WITH (NOLOCK)
        ON sps.function_id = spf.function_id
    LEFT JOIN sys.partition_range_values AS prv WITH (NOLOCK)
        ON spf.function_id = prv.function_id
    GROUP BY sps.name
        , spf.name
        , sps.data_space_id;';
    /*  
        sp_foreachdb was written by SQL MVP Aaron Bertrand and can be downloaded 
        at http://www.mssqltips.com/sqlservertip/2201/making-a-more-reliable-and-flexible-spmsforeachdb/
        Alternatively, you can also use sys.sp_MSforeachdb
    */
     
    /* Make sure we're not missing any major databases */
    SELECT * FROM sys.databases WHERE name NOT IN (SELECT databaseName FROM #Results);
     
    /* Retrieve our results */
    SELECT * 
    FROM #Results
    WHERE schemaName IS NOT NULL
    ORDER BY maxRangeValue;

    Example Results:

    databaseName        schemaName                      functionName                          data_space_id   maxRangeValue
    ------------------- ------------------------------- ------------------------------------- --------------- -------------------------
    HistoricalMart      dailyRangeDate_ps               dailyRangeDate_pf                     65609           2011-12-31 00:00:00.000
    AdventureWorks      yearlyRangeSmallDateTime_ps     yearlyRangeSmallDateTime_pf           65605           2012-01-01 00:00:00.000
    dbaTools            monthlyRangeDateTime_ps         monthlyRangeDateTime_pf               65604           2012-12-01 00:00:00.000
  3. How To Estimate Data Utilization

    Recently, on a conference call presenting data growth rates and database capacity projections, I had a top-line executive ask, "But how much of that data are we actually using today?" The question was met with silence; unless you have rigorous auditing in place -- and kudos to you if you do -- it's a difficult question to answer. But it begs the question, is there some way to gleam this information from SQL Server? I think the answer is "yes," if you make some assumptions and understand what you're looking at.

    SQL Server collects stats about every time an index is used and how it is used (i.e. whether a user seeked or scanned the index, etc.). It also provides a DMV to view these stats: sys.dm_db_index_usage_stats.

    This DMV provides a wealth of great information, but to answer our question of "What data is actually being used?", we have to refine our criteria. Are we talking in terms of table counts or data size? I'd argue that data size is more important than table counts; one unqueried millow-row table is more wasteful than a hundred ten-row tables.

    Also, are we looking at indexes or content? From a database perspective, I'm more interested in indexes: how much space are we wasting on unused indexes? To identify this, I need to look at the activity on each individual index.

    From a business perspective, I would be more interested in content (i.e. tables): how much business information is being stored that no one is even looking at? To answer this question, I need to roll up all index usage to see if *any* of the indexes on a table were used. Since both were of interest to me, I decided to write queries to answer both questions.

    Lastly, we need to understand the flaws with this data. Chiefly, I cannot tell whether a user requested one row from a million-row table, or if [s]he needed all of the data in the table. This is a pretty important issue, especially with large historical data stores, and it's where I have to make the biggest assumption: if even one person looked at one row in the table, I count all pages in the table as having been accessed.

    Now, you may make different decisions than I did above, and that's fine... each environment and project has different needs. But these assumptions are very important to understanding the output of the query below:

    USE master;
    GO
     
    /* 
        This will give you an approximation of how much data is being utilized on a server.
        Since the data is only valid as of the last server reboot, we should start off with
        an idea of how much data we've accrued.  
    */
     
    /* Find out when the server was last rebooted */
    -- 2008
    SELECT sqlserver_start_time FROM sys.dm_os_sys_info;
    -- 2005
    SELECT create_date FROM sys.databases WHERE name = 'tempdb';
     
     
    /* Create a temporary table to hold our data, since we're going to iterate through databases */
    IF OBJECT_ID('tempdb..#Results') IS NOT NULL
        DROP TABLE #Results;
     
    CREATE TABLE #Results
    (
          databaseName  NVARCHAR(128)
        , tableName     NVARCHAR(128)
        , indexID       INT
        , records       BIGINT
        , activity      BIGINT
        , totalPages    BIGINT
    );
     
    /*  
        sp_foreachdb was written by SQL MVP Aaron Bertrand and can be downloaded 
        at http://www.mssqltips.com/sqlservertip/2201/making-a-more-reliable-and-flexible-spmsforeachdb/
        Alternatively, you can also use sys.sp_MSforeachdb
    */
    --EXECUTE master.dbo.sp_foreachdb
    EXECUTE sys.sp_MSforeachdb
    '   USE ?; 
     
        -- You can gleam a lot of information about historical data usage from partitions
        -- but for now, we will just roll up any partitions we may have
        WITH myCTE AS
        (
            SELECT p.[object_id] AS objectID
                , p.index_id
                , SUM(p.[rows]) AS records
                , SUM(au.total_pages) AS totalPages
            FROM sys.partitions AS p WITH (NOLOCK)
            JOIN sys.allocation_units AS au WITH (NOLOCK)
                ON p.hobt_id = au.container_id
            GROUP BY p.[object_id] 
                , p.index_id
        )
     
        -- Grab all tables and join to our usage stats DMV
        INSERT INTO #Results
        SELECT DB_NAME() AS databaseName
            , t.name
            , x.index_id
            , MAX(x.records) AS records
            , ISNULL(SUM(us.user_lookups + us.user_scans + us.user_seeks), 0) AS activity
            , SUM(x.totalPages) AS totalPages
        FROM sys.tables AS t WITH (NOLOCK)
        JOIN myCTE AS x
            ON t.[object_id] = x.objectID
        LEFT JOIN sys.dm_db_index_usage_stats AS us WITH (NOLOCK)
            ON us.[object_id] = x.objectID
            AND us.index_id = x.index_id
            AND us.database_id = DB_ID()
        GROUP BY t.name
        , x.index_id;'
     
    /* Because we're looping through databases, make sure we're not missing any major ones */
    SELECT * FROM sys.databases WHERE name NOT IN (SELECT databaseName FROM #Results);
     
    /* Retrieve actual % data utilization, which is performed at the index level */
    SELECT databaseName
        , SUM(queriedPages) AS TotalQueriedPages
        , SUM(totalPages) AS TotalPages
        , CAST(SUM(queriedPages) AS FLOAT) / REPLACE(SUM(totalPages), 0, 1) AS '%DataUtil'
    FROM (
        SELECT databaseName
            , tableName
            , indexID
            , CASE -- If we have any activity at all on an index, count it as activity
                WHEN activity = 0 THEN 0.0
                ELSE totalPages
              END AS queriedPages
            , totalPages
        FROM #Results
        WHERE databaseName NOT IN ('master', 'tempdb', 'msdb', 'model')
    ) x
    GROUP BY databaseName
    ORDER BY databaseName;
     
    /* Retrieve % content utilization, which is performed at the table level */
    SELECT databaseName
        , SUM(queriedPages) AS TotalQueriedPages
        , SUM(totalPages) AS TotalPages
        , CAST(SUM(queriedPages) AS FLOAT) / REPLACE(SUM(totalPages), 0, 1) AS '%ContentUtil'
    FROM (
        SELECT databaseName
            , tableName
            , MAX(records) AS records
            , CASE WHEN SUM(activity) > 0 THEN SUM(totalPages) ELSE 0 END AS queriedPages
            , SUM(totalPages) AS totalPages
        FROM #Results
        WHERE databaseName NOT IN ('master', 'tempdb', 'msdb', 'model')
        GROUP BY databaseName
            , tableName
    ) x
    GROUP BY databaseName
    ORDER BY databaseName;

    Results:

    databaseName               TotalQueriedPages   TotalPages           %DataUtil
    -------------------------- ------------------- -------------------- ----------------------
    Database1 		   127618701           130607247            0.969619893356378
    Database2 		   567188              1614958              0.351209133612143
    Database3 		   34269036            34579469             0.991022620966216
    Database4 		   137970594           170733391            0.803399928206158
    Database5 		   74632930            101543575            0.66909214627557
    Database6 		   55809933            72884205             0.765734157938039
    Database7 		   560810026           620609815            0.902175272517656
     
    databaseName               TotalQueriedPages   TotalPages           %ContentUtil
    -------------------------- ------------------- -------------------- ----------------------
    Database1 		   127763715           130607247            0.970721679051682
    Database2 		   571125              1614958              0.353646967908763
    Database3 		   34269036            34579469             0.991022620966216
    Database4 		   137970921           170733391            0.803399928206158
    Database5 		   96144726            101543575            0.861947682777784
    Database6 		   72269666            72884205             0.991568146820268
    Database7 		   620525938           620609815            0.998240279711804

    The first result set examines the utilization of indexes, and the second result set examines the utilization of data at the content (table) level. For example, if we look at Database6, we'll see that we are only utilizing 77% of our indexes, but we're looking at 99% of our table data. So this is a good indicator that we have some unused indexes to clean up in that database.

    Know a better way to answer this question using SQL Server DMV's? Please leave me a comment so I can learn from your experience. :)

    In unrelated news, this may be my last blog post for a little while. I'm due with my second child a week from today and expect all of my free time to be consumed by him for a little while. That and, quite frankly, I do not trust myself near a computer, especially a database, in such a sleep-deprived state. :)

  4. East Iowa SQL Saturday is Next Saturday! (Oct 1st)

    East Iowa's 3rd annual SQL Saturday is right around the corner! This year's event will be on Saturday, October 1st. It's being held in the same location as previous years, at the University of Iowa Capitol Centre in Iowa City.

    We have a great mix of speakers this year, including nationally-recognized speakers such as Jason Strate and Ted Krueger. Topics include Denali, PowerPivot, High Availability, Disaster Recovery, PowerShell, SSIS, Analysis Services, Reporting Services, database tuning, and more. Don't miss out on this great opportunity to network with SQL-savvy locals while receiving FREE training.

    If you haven't registered yet, please do so we can make sure we order enough food. Oh, and make sure to stick around for the after-party, too. The after-party is one of my favorite parts of the whole event. This year's party will be held at The Mill, which is within walking distance of the conference center.

    I hope to see you there! :)

  5. Calculate Rows Inserted per Second for All Tables

    Ever needed to calculate the number of rows inserted every second, for every table in every database on a server? Or, have you ever needed to validate that all processes have stopped writing to tables? These types of questions come up routinely for me. To help with this, I've written the following script, which examines metadata values using sys.partitions. This method isn't as accurate as running SELECT COUNT(*) FROM, but it's much faster. Keep in mind, since it's just looking at row counts, it's not much help on tables that have a lot of update/delete activity. But it does what I need it to do, and I use it pretty regularly, so I thought I'd share in case anyone else can benefit from it too. :)

    /* Declare Parameters */
    DECLARE @newBaseline BIT = 1 -- change to 0 when you don't want to replace the baseline, i.e. after initial run
      , @delay CHAR(8) = '00:00:30'; -- change as needed
     
    IF @newBaseline = 1 
    BEGIN
        IF OBJECT_ID('tempdb..#baseline') IS NOT NULL
            DROP TABLE #baseline;
     
        CREATE TABLE #baseline
        (
             database_name  SYSNAME
           , table_name     SYSNAME
           , table_rows     BIGINT
           , captureTime    DATETIME NULL
        );
    END
     
    IF OBJECT_ID('tempdb..#current') IS NOT NULL
        DROP TABLE #current;
     
    CREATE TABLE #current
    (
         database_name  SYSNAME
       , table_name     SYSNAME
       , table_rows     BIGINT
       , captureTime    DATETIME NULL
    );
     
    IF @newBaseline = 1 
    BEGIN
        EXECUTE sp_MSforeachdb 'USE ?; 
            INSERT INTO #baseline
            SELECT DB_NAME()
                , o.name As [tableName]
                , SUM(p.[rows]) As [rowCnt]
                , GETDATE() As [captureTime]
            FROM sys.indexes As i
            JOIN sys.partitions As p
                ON i.[object_id] = p.[object_id]
               AND i.index_id  = p.index_id
            JOIN sys.objects As o
                ON i.[object_id] = o.[object_id]
            WHERE i.[type] = 1
            GROUP BY o.name;'
     
        WAITFOR DELAY @delay;
    END
     
    EXECUTE sp_MSforeachdb 'USE ?; 
    INSERT INTO #current
    SELECT DB_NAME()
        , o.name As [tableName]
        , SUM(p.[rows]) As [rowCnt]
        , GETDATE() As [captureTime]
    FROM sys.indexes As i
    JOIN sys.partitions As p
        ON i.[object_id] = p.[object_id]
       AND i.index_id  = p.index_id
    JOIN sys.objects As o
        ON i.[object_id] = o.[object_id]
    WHERE i.[type] = 1
    GROUP BY o.name;'
     
    SELECT  c.*
          , c.table_rows - b.table_rows AS 'new_rows'
          , DATEDIFF(second, b.captureTime, c.captureTime) AS 'time_diff'
          , (c.table_rows - b.table_rows) / DATEDIFF(second, b.captureTime, c.captureTime) AS 'rows_per_sec'
    FROM #baseline AS b
    JOIN #current AS c
        ON b.table_name = c.table_name
       AND b.database_name = c.database_name
    ORDER BY new_rows DESC;
  6. Index Defrag Script, v4.1

    It's been quite some time since my last index defrag script update. A big part of the reason for that is because I wanted to implement many of the suggestions I've received, but I just haven't had the time. I still have those changes planned, but I'm not sure quite when I'll get to it. Rather than continue to wait for a major release, I'm releasing a small update to my defrag that will take care of the most common complaints I receive.

    Change Log:

    • Bug fix for databases containing spaces or special characters
    • Support for case-sensitive databases
    • Re-executable CREATE script (for those who want to re-run the whole script)
    • Comma-delimited list of databases is now supported for the @database parameter

    Feature List:

    • Defrag a single database, a list of databases, or all databases (@database)
    • Time Limitations: stop defragging after the specified amount of time has elapsed (@timeLimit). Please note, it will not kill a defrag that is currently in process, even if it exceeds the threshold.
    • Optional stop-and-resume functionality: pick up where your defrag last left off without having to rescan sys.dm_db_index_physical_stats. (@forceRescan)
    • Defrag scheduling: choose which days to defrag certain indexes, or exclude certain indexes altogether, by using the dbo.dba_indexDefragExclusion table.
    • Defrag priority: choose whether to defrag indexes in ascending or descending order by range_scan_count (default), fragmentation, or page_count.
    • Current partition exclusion: choose whether or not to exclude the right-most populated partition from the defrag process, common for sliding-window tables (@excludeMaxPartition)
    • Commands-only mode: Choose to just log the current defrag status and print the defrag commands, rather than executing them, by using @executeSQL.
    • ... and tons more! Please read the parameter list and notes section for details of all the options available.

    FAQ:

    I often receive the same questions about this script, so allow me to answer them here:

    "I keep running the script, but my index is still fragmented. Why?"
    This is most likely a very small index. Here's what Microsoft has to say:

    "In general, fragmentation on small indexes is often not controllable. The pages of small indexes are stored on mixed extents. Mixed extents are shared by up to eight objects, so the fragmentation in a small index might not be reduced after reorganizing or rebuilding the index. For more information about mixed extents, see Understanding Pages and Extents."

    "What database should I create it in?" or "Can I create this in the MASTER database?"
    It's up to you where you create it. You could technically create it in the MASTER database, but I recommend creating a utility database for your DBA administrative tasks.

    "Can I run this againt a SharePoint database?"
    Yes, you can.

    "What are the minimum requirements to run this script?" or "Will this run on SQL Server 2000 instances?"
    You need to be on SQL Server 2005 SP2 or higher.

    Special thanks to Richard Yanger for his assistance with beta testing. :)

    You can download a text file of this script here: dba_indexDefrag_sp_v41

    /*** Scroll down to the see important notes, disclaimers, and licensing information ***/
     
    /* Let's create our parsing function... */
    IF EXISTS ( SELECT  [object_id]
                FROM    sys.objects
                WHERE   name = 'dba_parseString_udf' )
        DROP FUNCTION dbo.dba_parseString_udf;
    GO
     
    CREATE FUNCTION dbo.dba_parseString_udf
    (
              @stringToParse VARCHAR(8000)  
            , @delimiter     CHAR(1)
    )
    RETURNS @parsedString TABLE (stringValue VARCHAR(128))
    AS
    /*********************************************************************************
        Name:       dba_parseString_udf
     
        Author:     Michelle Ufford, http://sqlfool.com
     
        Purpose:    This function parses string input using a variable delimiter.
     
        Notes:      Two common delimiter values are space (' ') and comma (',')
     
        Date        Initials    Description
        ----------------------------------------------------------------------------
        2011-05-20  MFU         Initial Release
    *********************************************************************************
    Usage: 		
        SELECT *
        FROM dba_parseString_udf(<string>, <delimiter>);
     
    Test Cases:
     
        1.  multiple strings separated by space
            SELECT * FROM dbo.dba_parseString_udf('  aaa  bbb  ccc ', ' ');
     
        2.  multiple strings separated by comma
            SELECT * FROM dbo.dba_parseString_udf(',aaa,bbb,,,ccc,', ',');
    *********************************************************************************/
    BEGIN
     
        /* Declare variables */
        DECLARE @trimmedString  VARCHAR(8000);
     
        /* We need to trim our string input in case the user entered extra spaces */
        SET @trimmedString = LTRIM(RTRIM(@stringToParse));
     
        /* Let's create a recursive CTE to break down our string for us */
        WITH parseCTE (StartPos, EndPos)
        AS
        (
            SELECT 1 AS StartPos
                , CHARINDEX(@delimiter, @trimmedString + @delimiter) AS EndPos
            UNION ALL
            SELECT EndPos + 1 AS StartPos
                , CHARINDEX(@delimiter, @trimmedString + @delimiter , EndPos + 1) AS EndPos
            FROM parseCTE
            WHERE CHARINDEX(@delimiter, @trimmedString + @delimiter, EndPos + 1) <> 0
        )
     
        /* Let's take the results and stick it in a table */  
        INSERT INTO @parsedString
        SELECT SUBSTRING(@trimmedString, StartPos, EndPos - StartPos)
        FROM parseCTE
        WHERE LEN(LTRIM(RTRIM(SUBSTRING(@trimmedString, StartPos, EndPos - StartPos)))) > 0
        OPTION (MaxRecursion 8000);
     
        RETURN;   
    END
    GO
     
    /* First, we need to take care of schema updates, in case you have a legacy 
       version of the script installed */
    DECLARE @indexDefragLog_rename      VARCHAR(128)
      , @indexDefragExclusion_rename    VARCHAR(128)
      , @indexDefragStatus_rename       VARCHAR(128);
     
    SELECT  @indexDefragLog_rename = 'dba_indexDefragLog_obsolete_' + CONVERT(VARCHAR(10), GETDATE(), 112)
          , @indexDefragExclusion_rename = 'dba_indexDefragExclusion_obsolete_' + CONVERT(VARCHAR(10), GETDATE(), 112);
     
    IF EXISTS ( SELECT  [object_id]
                FROM    sys.indexes
                WHERE   name = 'PK_indexDefragLog' ) 
        EXECUTE sp_rename dba_indexDefragLog, @indexDefragLog_rename;
     
    IF EXISTS ( SELECT  [object_id]
                FROM    sys.indexes
                WHERE   name = 'PK_indexDefragExclusion' ) 
        EXECUTE sp_rename dba_indexDefragExclusion, @indexDefragExclusion_rename;
     
    IF NOT EXISTS ( SELECT  [object_id]
                    FROM    sys.indexes
                    WHERE   name = 'PK_indexDefragLog_v40' )
    BEGIN
     
        CREATE TABLE dbo.dba_indexDefragLog
        (
             indexDefrag_id     INT IDENTITY(1, 1)  NOT NULL
           , databaseID         INT                 NOT NULL
           , databaseName       NVARCHAR(128)       NOT NULL
           , objectID           INT                 NOT NULL
           , objectName         NVARCHAR(128)       NOT NULL
           , indexID            INT                 NOT NULL
           , indexName          NVARCHAR(128)       NOT NULL
           , partitionNumber    SMALLINT            NOT NULL
           , fragmentation      FLOAT               NOT NULL
           , page_count         INT                 NOT NULL
           , dateTimeStart      DATETIME            NOT NULL
           , dateTimeEnd        DATETIME            NULL
           , durationSeconds    INT                 NULL
           , sqlStatement       VARCHAR(4000)       NULL
           , errorMessage       VARCHAR(1000)       NULL 
     
            CONSTRAINT PK_indexDefragLog_v40 
                PRIMARY KEY CLUSTERED (indexDefrag_id)
        );
     
        PRINT 'dba_indexDefragLog Table Created';
     
    END
     
    IF NOT EXISTS ( SELECT  [object_id]
                    FROM    sys.indexes
                    WHERE   name = 'PK_indexDefragExclusion_v40' )
    BEGIN
     
        CREATE TABLE dbo.dba_indexDefragExclusion
        (
             databaseID         INT             NOT NULL
           , databaseName       NVARCHAR(128)   NOT NULL
           , objectID           INT             NOT NULL
           , objectName         NVARCHAR(128)   NOT NULL
           , indexID            INT             NOT NULL
           , indexName          NVARCHAR(128)   NOT NULL
           , exclusionMask      INT             NOT NULL
                /* 1=Sunday, 2=Monday, 4=Tuesday, 8=Wednesday, 16=Thursday, 32=Friday, 64=Saturday */
     
             CONSTRAINT PK_indexDefragExclusion_v40 
                PRIMARY KEY CLUSTERED (databaseID, objectID, indexID)
        );
     
        PRINT 'dba_indexDefragExclusion Table Created';
     
    END
     
    IF NOT EXISTS ( SELECT  [object_id]
                    FROM    sys.indexes
                    WHERE   name = 'PK_indexDefragStatus_v40' )
    BEGIN
     
        CREATE TABLE dbo.dba_indexDefragStatus
        (
             databaseID         INT             NOT NULL
           , databaseName       NVARCHAR(128)   NOT NULL
           , objectID           INT             NOT NULL
           , indexID            INT             NOT NULL
           , partitionNumber    SMALLINT        NOT NULL
           , fragmentation      FLOAT           NOT NULL
           , page_count         INT             NOT NULL
           , range_scan_count   BIGINT          NOT NULL
           , schemaName         NVARCHAR(128)   NULL
           , objectName         NVARCHAR(128)   NULL
           , indexName          NVARCHAR(128)   NULL
           , scanDate           DATETIME        NOT NULL
           , defragDate         DATETIME        NULL
           , printStatus        BIT DEFAULT (0) NOT NULL
           , exclusionMask      INT DEFAULT (0) NOT NULL
     
            CONSTRAINT PK_indexDefragStatus_v40 
                PRIMARY KEY CLUSTERED (databaseID, objectID, indexID, partitionNumber)
        );
     
        PRINT 'dba_indexDefragStatus Table Created';
     
    END;
     
    IF OBJECTPROPERTY(OBJECT_ID('dbo.dba_indexDefrag_sp'), N'IsProcedure') = 1 
        BEGIN
            DROP PROCEDURE dbo.dba_indexDefrag_sp;
            PRINT 'Procedure dba_indexDefrag_sp dropped';
        END;
    Go
     
    CREATE PROCEDURE dbo.dba_indexDefrag_sp
     
        /* Declare Parameters */
        @minFragmentation       FLOAT               = 10.0  
            /* in percent, will not defrag if fragmentation less than specified */
      , @rebuildThreshold       FLOAT               = 30.0  
            /* in percent, greater than @rebuildThreshold will result in rebuild instead of reorg */
      , @executeSQL             BIT                 = 1     
            /* 1 = execute; 0 = print command only */
      , @defragOrderColumn      NVARCHAR(20)        = 'range_scan_count'
            /* Valid options are: range_scan_count, fragmentation, page_count */
      , @defragSortOrder        NVARCHAR(4)         = 'DESC'
            /* Valid options are: ASC, DESC */
      , @timeLimit              INT                 = 720 /* defaulted to 12 hours */
            /* Optional time limitation; expressed in minutes */
      , @database               VARCHAR(128)        = NULL
            /* Option to specify one or more database names, separated by commas; NULL will return all */
      , @tableName              VARCHAR(4000)       = NULL  -- databaseName.schema.tableName
            /* Option to specify a table name; null will return all */
      , @forceRescan            BIT                 = 0
            /* Whether or not to force a rescan of indexes; 1 = force, 0 = use existing scan, if available */
      , @scanMode               VARCHAR(10)         = N'LIMITED'
            /* Options are LIMITED, SAMPLED, and DETAILED */
      , @minPageCount           INT                 = 8 
            /*  MS recommends > 1 extent (8 pages) */
      , @maxPageCount           INT                 = NULL
            /* NULL = no limit */
      , @excludeMaxPartition    BIT                 = 0
            /* 1 = exclude right-most populated partition; 0 = do not exclude; see notes for caveats */
      , @onlineRebuild          BIT                 = 1     
            /* 1 = online rebuild; 0 = offline rebuild; only in Enterprise */
      , @sortInTempDB           BIT                 = 1
            /* 1 = perform sort operation in TempDB; 0 = perform sort operation in the index's database */
      , @maxDopRestriction      TINYINT             = NULL
            /* Option to restrict the number of processors for the operation; only in Enterprise */
      , @printCommands          BIT                 = 0     
            /* 1 = print commands; 0 = do not print commands */
      , @printFragmentation     BIT                 = 0
            /* 1 = print fragmentation prior to defrag; 
               0 = do not print */
      , @defragDelay            CHAR(8)             = '00:00:05'
            /* time to wait between defrag commands */
      , @debugMode              BIT                 = 0
            /* display some useful comments to help determine if/WHERE issues occur */
    AS /*********************************************************************************
        Name:       dba_indexDefrag_sp
     
        Author:     Michelle Ufford, http://sqlfool.com
     
        Purpose:    Defrags one or more indexes for one or more databases
     
        Notes:
     
        CAUTION: TRANSACTION LOG SIZE SHOULD BE MONITORED CLOSELY WHEN DEFRAGMENTING.
                 DO NOT RUN UNATTENDED ON LARGE DATABASES DURING BUSINESS HOURS.
     
          @minFragmentation     defaulted to 10%, will not defrag if fragmentation 
                                is less than that
     
          @rebuildThreshold     defaulted to 30% AS recommended by Microsoft in BOL;
                                greater than 30% will result in rebuild instead
     
          @executeSQL           1 = execute the SQL generated by this proc; 
                                0 = print command only
     
          @defragOrderColumn    Defines how to prioritize the order of defrags.  Only
                                used if @executeSQL = 1.  
                                Valid options are: 
                                range_scan_count = count of range and table scans on the
                                                   index; in general, this is what benefits 
                                                   the most FROM defragmentation
                                fragmentation    = amount of fragmentation in the index;
                                                   the higher the number, the worse it is
                                page_count       = number of pages in the index; affects
                                                   how long it takes to defrag an index
     
          @defragSortOrder      The sort order of the ORDER BY clause.
                                Valid options are ASC (ascending) or DESC (descending).
     
          @timeLimit            Optional, limits how much time can be spent performing 
                                index defrags; expressed in minutes.
     
                                NOTE: The time limit is checked BEFORE an index defrag
                                      is begun, thus a long index defrag can exceed the
                                      time limitation.
     
          @database             Optional, specify specific database name to defrag;
                                If not specified, all non-system databases will
                                be defragged.
     
          @tableName            Specify if you only want to defrag indexes for a 
                                specific table, format = databaseName.schema.tableName;
                                if not specified, all tables will be defragged.
     
          @forceRescan          Whether or not to force a rescan of indexes.  If set
                                to 0, a rescan will not occur until all indexes have
                                been defragged.  This can span multiple executions.
                                1 = force a rescan
                                0 = use previous scan, if there are indexes left to defrag
     
          @scanMode             Specifies which scan mode to use to determine
                                fragmentation levels.  Options are:
                                LIMITED - scans the parent level; quickest mode,
                                          recommended for most cases.
                                SAMPLED - samples 1% of all data pages; if less than
                                          10k pages, performs a DETAILED scan.
                                DETAILED - scans all data pages.  Use great care with
                                           this mode, AS it can cause performance issues.
     
          @minPageCount         Specifies how many pages must exist in an index in order 
                                to be considered for a defrag.  Defaulted to 8 pages, AS 
                                Microsoft recommends only defragging indexes with more 
                                than 1 extent (8 pages).  
     
                                NOTE: The @minPageCount will restrict the indexes that
                                are stored in dba_indexDefragStatus table.
     
          @maxPageCount         Specifies the maximum number of pages that can exist in 
                                an index and still be considered for a defrag.  Useful
                                for scheduling small indexes during business hours and
                                large indexes for non-business hours.
     
                                NOTE: The @maxPageCount will restrict the indexes that
                                are defragged during the current operation; it will not
                                prevent indexes FROM being stored in the 
                                dba_indexDefragStatus table.  This way, a single scan
                                can support multiple page count thresholds.
     
          @excludeMaxPartition  If an index is partitioned, this option specifies whether
                                to exclude the right-most populated partition.  Typically,
                                this is the partition that is currently being written to in
                                a sliding-window scenario.  Enabling this feature may reduce
                                contention.  This may not be applicable in other types of 
                                partitioning scenarios.  Non-partitioned indexes are 
                                unaffected by this option.
                                1 = exclude right-most populated partition
                                0 = do not exclude
     
          @onlineRebuild        1 = online rebuild; 
                                0 = offline rebuild
     
          @sortInTempDB         Specifies whether to defrag the index in TEMPDB or in the
                                database the index belongs to.  Enabling this option may
                                result in faster defrags and prevent database file size 
                                inflation.
                                1 = perform sort operation in TempDB
                                0 = perform sort operation in the index's database 
     
          @maxDopRestriction    Option to specify a processor limit for index rebuilds
     
          @printCommands        1 = print commands to screen; 
                                0 = do not print commands
     
          @printFragmentation   1 = print fragmentation to screen;
                                0 = do not print fragmentation
     
          @defragDelay          Time to wait between defrag commands; gives the
                                server a little time to catch up 
     
          @debugMode            1 = display debug comments; helps with troubleshooting
                                0 = do not display debug comments
     
        Called by:  SQL Agent Job or DBA
     
        ----------------------------------------------------------------------------
        DISCLAIMER: 
        This code and information are provided "AS IS" without warranty of any kind,
        either expressed or implied, including but not limited to the implied 
        warranties or merchantability and/or fitness for a particular purpose.
        ----------------------------------------------------------------------------
        LICENSE: 
        This index defrag script is free to download and use for personal, educational, 
        and internal corporate purposes, provided that this header is preserved. 
        Redistribution or sale of this index defrag script, in whole or in part, is 
        prohibited without the author's express written consent.
        ----------------------------------------------------------------------------
        Date        Initials	Version Description
        ----------------------------------------------------------------------------
        2007-12-18  MFU         1.0     Initial Release
        2008-10-17  MFU         1.1     Added @defragDelay, CIX_temp_indexDefragList
        2008-11-17  MFU         1.2     Added page_count to log table
                                        , added @printFragmentation option
        2009-03-17  MFU         2.0     Provided support for centralized execution
                                        , consolidated Enterprise & Standard versions
                                        , added @debugMode, @maxDopRestriction
                                        , modified LOB and partition logic  
        2009-06-18  MFU         3.0     Fixed bug in LOB logic, added @scanMode option
                                        , added support for stat rebuilds (@rebuildStats)
                                        , support model and msdb defrag
                                        , added columns to the dba_indexDefragLog table
                                        , modified logging to show "in progress" defrags
                                        , added defrag exclusion list (scheduling)
        2009-08-28  MFU         3.1     Fixed read_only bug for database lists
        2010-04-20  MFU         4.0     Added time limit option
                                        , added static table with rescan logic
                                        , added parameters for page count & SORT_IN_TEMPDB
                                        , added try/catch logic and additional debug options
                                        , added options for defrag prioritization
                                        , fixed bug for indexes with allow_page_lock = off
                                        , added option to exclude right-most partition
                                        , removed @rebuildStats option
                                        , refer to http://sqlfool.com for full release notes
        2011-04-28  MFU         4.1     Bug fixes for databases requiring []
                                        , cleaned up the create table section
                                        , updated syntax for case-sensitive databases
                                        , comma-delimited list for @database now supported
    *********************************************************************************
        Example of how to call this script:
     
            EXECUTE dbo.dba_indexDefrag_sp
                  @executeSQL           = 1
                , @printCommands        = 1
                , @debugMode            = 1
                , @printFragmentation   = 1
                , @forceRescan          = 1
                , @maxDopRestriction    = 1
                , @minPageCount         = 8
                , @maxPageCount         = NULL
                , @minFragmentation     = 1
                , @rebuildThreshold     = 30
                , @defragDelay          = '00:00:05'
                , @defragOrderColumn    = 'page_count'
                , @defragSortOrder      = 'DESC'
                , @excludeMaxPartition  = 1
                , @timeLimit            = NULL
                , @database             = 'sandbox,sandbox_caseSensitive';
    *********************************************************************************/																
    SET NOCOUNT ON;
    SET XACT_ABORT ON;
    SET QUOTED_IDENTIFIER ON;
     
    BEGIN
     
        BEGIN TRY
     
            /* Just a little validation... */
            IF @minFragmentation IS NULL 
                OR @minFragmentation NOT BETWEEN 0.00 AND 100.0
                    SET @minFragmentation = 10.0;
     
            IF @rebuildThreshold IS NULL
                OR @rebuildThreshold NOT BETWEEN 0.00 AND 100.0
                    SET @rebuildThreshold = 30.0;
     
            IF @defragDelay NOT LIKE '00:[0-5][0-9]:[0-5][0-9]'
                SET @defragDelay = '00:00:05';
     
            IF @defragOrderColumn IS NULL
                OR @defragOrderColumn NOT IN ('range_scan_count', 'fragmentation', 'page_count')
                    SET @defragOrderColumn = 'range_scan_count';
     
            IF @defragSortOrder IS NULL
                OR @defragSortOrder NOT IN ('ASC', 'DESC')
                    SET @defragSortOrder = 'DESC';
     
            IF @scanMode NOT IN ('LIMITED', 'SAMPLED', 'DETAILED')
                SET @scanMode = 'LIMITED';
     
            IF @debugMode IS NULL
                SET @debugMode = 0;
     
            IF @forceRescan IS NULL
                SET @forceRescan = 0;
     
            IF @sortInTempDB IS NULL
                SET @sortInTempDB = 1;
     
     
            IF @debugMode = 1 RAISERROR('Undusting the cogs AND starting up...', 0, 42) WITH NOWAIT;
     
            /* Declare our variables */
            DECLARE   @objectID                 INT
                    , @databaseID               INT
                    , @databaseName             NVARCHAR(128)
                    , @indexID                  INT
                    , @partitionCount           BIGINT
                    , @schemaName               NVARCHAR(128)
                    , @objectName               NVARCHAR(128)
                    , @indexName                NVARCHAR(128)
                    , @partitionNumber          SMALLINT
                    , @fragmentation            FLOAT
                    , @pageCount                INT
                    , @sqlCommand               NVARCHAR(4000)
                    , @rebuildCommand           NVARCHAR(200)
                    , @datetimestart            DATETIME
                    , @dateTimeEnd              DATETIME
                    , @containsLOB              BIT
                    , @editionCheck             BIT
                    , @debugMessage             NVARCHAR(4000)
                    , @updateSQL                NVARCHAR(4000)
                    , @partitionSQL             NVARCHAR(4000)
                    , @partitionSQL_Param       NVARCHAR(1000)
                    , @LOB_SQL                  NVARCHAR(4000)
                    , @LOB_SQL_Param            NVARCHAR(1000)
                    , @indexDefrag_id           INT
                    , @startdatetime            DATETIME
                    , @enddatetime              DATETIME
                    , @getIndexSQL              NVARCHAR(4000)
                    , @getIndexSQL_Param        NVARCHAR(4000)
                    , @allowPageLockSQL         NVARCHAR(4000)
                    , @allowPageLockSQL_Param   NVARCHAR(4000)
                    , @allowPageLocks           INT
                    , @excludeMaxPartitionSQL   NVARCHAR(4000);
     
            /* Initialize our variables */
            SELECT @startdatetime = GETDATE()
                , @enddatetime = DATEADD(minute, @timeLimit, GETDATE());
     
            /* Create our temporary tables */
            CREATE TABLE #databaseList
            (
                  databaseID        INT
                , databaseName      VARCHAR(128)
                , scanStatus        BIT
            );
     
            CREATE TABLE #processor 
            (
                  [index]           INT
                , Name              VARCHAR(128)
                , Internal_Value    INT
                , Character_Value   INT
            );
     
            CREATE TABLE #maxPartitionList
            (
                  databaseID        INT
                , objectID          INT
                , indexID           INT
                , maxPartition      INT
            );
     
            IF @debugMode = 1 RAISERROR('Beginning validation...', 0, 42) WITH NOWAIT;
     
            /* Make sure we're not exceeding the number of processors we have available */
            INSERT INTO #processor
            EXECUTE xp_msver 'ProcessorCount';
     
            IF @maxDopRestriction IS NOT NULL AND @maxDopRestriction > (SELECT Internal_Value FROM #processor)
                SELECT @maxDopRestriction = Internal_Value
                FROM #processor;
     
            /* Check our server version; 1804890536 = Enterprise, 610778273 = Enterprise Evaluation, -2117995310 = Developer */
            IF (SELECT ServerProperty('EditionID')) IN (1804890536, 610778273, -2117995310) 
                SET @editionCheck = 1 -- supports online rebuilds
            ELSE
                SET @editionCheck = 0; -- does not support online rebuilds
     
            /* Output the parameters we're working with */
            IF @debugMode = 1 
            BEGIN
     
                SELECT @debugMessage = 'Your SELECTed parameters are... 
                Defrag indexes WITH fragmentation greater than ' + CAST(@minFragmentation AS VARCHAR(10)) + ';
                REBUILD indexes WITH fragmentation greater than ' + CAST(@rebuildThreshold AS VARCHAR(10)) + ';
                You' + CASE WHEN @executeSQL = 1 THEN ' DO' ELSE ' DO NOT' END + ' want the commands to be executed automatically; 
                You want to defrag indexes in ' + @defragSortOrder + ' order of the ' + UPPER(@defragOrderColumn) + ' value;
                You have' + CASE WHEN @timeLimit IS NULL THEN ' NOT specified a time limit;' ELSE ' specified a time limit of ' 
                    + CAST(@timeLimit AS VARCHAR(10)) END + ' minutes;
                ' + CASE WHEN @database IS NULL THEN 'ALL databases' ELSE 'The ' + @database + ' database(s)' END + ' will be defragged;
                ' + CASE WHEN @tableName IS NULL THEN 'ALL tables' ELSE 'The ' + @tableName + ' TABLE' END + ' will be defragged;
                We' + CASE WHEN EXISTS(SELECT Top 1 * FROM dbo.dba_indexDefragStatus WHERE defragDate IS NULL)
                    AND @forceRescan <> 1 THEN ' WILL NOT' ELSE ' WILL' END + ' be rescanning indexes;
                The scan will be performed in ' + @scanMode + ' mode;
                You want to limit defrags to indexes with' + CASE WHEN @maxPageCount IS NULL THEN ' more than ' 
                    + CAST(@minPageCount AS VARCHAR(10)) ELSE
                    ' BETWEEN ' + CAST(@minPageCount AS VARCHAR(10))
                    + ' AND ' + CAST(@maxPageCount AS VARCHAR(10)) END + ' pages;
                Indexes will be defragged' + CASE WHEN @editionCheck = 0 OR @onlineRebuild = 0 THEN ' OFFLINE;' ELSE ' ONLINE;' END + '
                Indexes will be sorted in' + CASE WHEN @sortInTempDB = 0 THEN ' the DATABASE' ELSE ' TEMPDB;' END + '
                Defrag operations will utilize ' + CASE WHEN @editionCheck = 0 OR @maxDopRestriction IS NULL 
                    THEN 'system defaults for processors;' 
                    ELSE CAST(@maxDopRestriction AS VARCHAR(2)) + ' processors;' END + '
                You' + CASE WHEN @printCommands = 1 THEN ' DO' ELSE ' DO NOT' END + ' want to PRINT the ALTER INDEX commands; 
                You' + CASE WHEN @printFragmentation = 1 THEN ' DO' ELSE ' DO NOT' END + ' want to OUTPUT fragmentation levels; 
                You want to wait ' + @defragDelay + ' (hh:mm:ss) BETWEEN defragging indexes;
                You want to run in' + CASE WHEN @debugMode = 1 THEN ' DEBUG' ELSE ' SILENT' END + ' mode.';
     
                RAISERROR(@debugMessage, 0, 42) WITH NOWAIT;
     
            END;
     
            IF @debugMode = 1 RAISERROR('Grabbing a list of our databases...', 0, 42) WITH NOWAIT;
     
            /* Retrieve the list of databases to investigate */
            /* If @database is NULL, it means we want to defrag *all* databases */
            IF @database IS NULL
            BEGIN
     
                INSERT INTO #databaseList
                SELECT database_id
                    , name
                    , 0 -- not scanned yet for fragmentation
                FROM sys.databases
                WHERE [name] NOT IN ('master', 'tempdb')-- exclude system databases
                    AND [state] = 0 -- state must be ONLINE
                    AND is_read_only = 0;  -- cannot be read_only
     
            END;
            ELSE
            /* Otherwise, we're going to just defrag our list of databases */
            BEGIN
     
                INSERT INTO #databaseList
                SELECT database_id
                    , name
                    , 0 -- not scanned yet for fragmentation
                FROM sys.databases AS d
                JOIN dbo.dba_parseString_udf(@database, ',') AS x
                    ON d.name = x.stringValue
                WHERE [name] NOT IN ('master', 'tempdb')-- exclude system databases
                    AND [state] = 0 -- state must be ONLINE
                    AND is_read_only = 0;  -- cannot be read_only
     
            END; 
     
            /* Check to see IF we have indexes in need of defrag; otherwise, re-scan the database(s) */
            IF NOT EXISTS(SELECT Top 1 * FROM dbo.dba_indexDefragStatus WHERE defragDate IS NULL)
                OR @forceRescan = 1
            BEGIN
     
                /* Truncate our list of indexes to prepare for a new scan */
                TRUNCATE TABLE dbo.dba_indexDefragStatus;
     
                IF @debugMode = 1 RAISERROR('Looping through our list of databases and checking for fragmentation...', 0, 42) WITH NOWAIT;
     
                /* Loop through our list of databases */
                WHILE (SELECT COUNT(*) FROM #databaseList WHERE scanStatus = 0) > 0
                BEGIN
     
                    SELECT Top 1 @databaseID = databaseID
                    FROM #databaseList
                    WHERE scanStatus = 0;
     
                    SELECT @debugMessage = '  working on ' + DB_NAME(@databaseID) + '...';
     
                    IF @debugMode = 1
                        RAISERROR(@debugMessage, 0, 42) WITH NOWAIT;
     
                   /* Determine which indexes to defrag using our user-defined parameters */
                    INSERT INTO dbo.dba_indexDefragStatus
                    (
                          databaseID
                        , databaseName
                        , objectID
                        , indexID
                        , partitionNumber
                        , fragmentation
                        , page_count
                        , range_scan_count
                        , scanDate
                    )
                    SELECT
                          ps.database_id AS 'databaseID'
                        , QUOTENAME(DB_NAME(ps.database_id)) AS 'databaseName'
                        , ps.[object_id] AS 'objectID'
                        , ps.index_id AS 'indexID'
                        , ps.partition_number AS 'partitionNumber'
                        , SUM(ps.avg_fragmentation_in_percent) AS 'fragmentation'
                        , SUM(ps.page_count) AS 'page_count'
                        , os.range_scan_count
                        , GETDATE() AS 'scanDate'
                    FROM sys.dm_db_index_physical_stats(@databaseID, OBJECT_ID(@tableName), NULL , NULL, @scanMode) AS ps
                    JOIN sys.dm_db_index_operational_stats(@databaseID, OBJECT_ID(@tableName), NULL , NULL) AS os
                        ON ps.database_id = os.database_id
                        AND ps.[object_id] = os.[object_id]
                        AND ps.index_id = os.index_id
                        AND ps.partition_number = os.partition_number
                    WHERE avg_fragmentation_in_percent >= @minFragmentation 
                        AND ps.index_id > 0 -- ignore heaps
                        AND ps.page_count > @minPageCount 
                        AND ps.index_level = 0 -- leaf-level nodes only, supports @scanMode
                    GROUP BY ps.database_id 
                        , QUOTENAME(DB_NAME(ps.database_id)) 
                        , ps.[object_id]
                        , ps.index_id 
                        , ps.partition_number 
                        , os.range_scan_count
                    OPTION (MAXDOP 2);
     
                    /* Do we want to exclude right-most populated partition of our partitioned indexes? */
                    IF @excludeMaxPartition = 1
                    BEGIN
     
                        SET @excludeMaxPartitionSQL = '
                            SELECT ' + CAST(@databaseID AS VARCHAR(10)) + ' AS [databaseID]
                                , [object_id]
                                , index_id
                                , MAX(partition_number) AS [maxPartition]
                            FROM [' + DB_NAME(@databaseID) + '].sys.partitions
                            WHERE partition_number > 1
                                AND [rows] > 0
                            GROUP BY object_id
                                , index_id;';
     
                        INSERT INTO #maxPartitionList
                        EXECUTE sp_executesql @excludeMaxPartitionSQL;
     
                    END;
     
                    /* Keep track of which databases have already been scanned */
                    UPDATE #databaseList
                    SET scanStatus = 1
                    WHERE databaseID = @databaseID;
     
                END
     
                /* We don't want to defrag the right-most populated partition, so
                   delete any records for partitioned indexes where partition = MAX(partition) */
                IF @excludeMaxPartition = 1
                BEGIN
     
                    DELETE ids
                    FROM dbo.dba_indexDefragStatus AS ids
                    JOIN #maxPartitionList AS mpl
                        ON ids.databaseID = mpl.databaseID
                        AND ids.objectID = mpl.objectID
                        AND ids.indexID = mpl.indexID
                        AND ids.partitionNumber = mpl.maxPartition;
     
                END;
     
                /* Update our exclusion mask for any index that has a restriction ON the days it can be defragged */
                UPDATE ids
                SET ids.exclusionMask = ide.exclusionMask
                FROM dbo.dba_indexDefragStatus AS ids
                JOIN dbo.dba_indexDefragExclusion AS ide
                    ON ids.databaseID = ide.databaseID
                    AND ids.objectID = ide.objectID
                    AND ids.indexID = ide.indexID;
     
            END
     
            SELECT @debugMessage = 'Looping through our list... there are ' + CAST(COUNT(*) AS VARCHAR(10)) + ' indexes to defrag!'
            FROM dbo.dba_indexDefragStatus
            WHERE defragDate IS NULL
                AND page_count BETWEEN @minPageCount AND ISNULL(@maxPageCount, page_count);
     
            IF @debugMode = 1 RAISERROR(@debugMessage, 0, 42) WITH NOWAIT;
     
            /* Begin our loop for defragging */
            WHILE (SELECT COUNT(*) 
                   FROM dbo.dba_indexDefragStatus 
                   WHERE (
                               (@executeSQL = 1 AND defragDate IS NULL) 
                            OR (@executeSQL = 0 AND defragDate IS NULL AND printStatus = 0)
                         )
                    AND exclusionMask & POWER(2, DATEPART(weekday, GETDATE())-1) = 0
                    AND page_count BETWEEN @minPageCount AND ISNULL(@maxPageCount, page_count)) > 0
            BEGIN
     
                /* Check to see IF we need to exit our loop because of our time limit */        
                IF ISNULL(@enddatetime, GETDATE()) < GETDATE()
                BEGIN
                    RAISERROR('Our time limit has been exceeded!', 11, 42) WITH NOWAIT;
                END;
     
                IF @debugMode = 1 RAISERROR('  Picking an index to beat into shape...', 0, 42) WITH NOWAIT;
     
                /* Grab the index with the highest priority, based on the values submitted; 
                   Look at the exclusion mask to ensure it can be defragged today */
                SET @getIndexSQL = N'
                SELECT TOP 1 
                      @objectID_Out         = objectID
                    , @indexID_Out          = indexID
                    , @databaseID_Out       = databaseID
                    , @databaseName_Out     = databaseName
                    , @fragmentation_Out    = fragmentation
                    , @partitionNumber_Out  = partitionNumber
                    , @pageCount_Out        = page_count
                FROM dbo.dba_indexDefragStatus
                WHERE defragDate IS NULL ' 
                    + CASE WHEN @executeSQL = 0 THEN 'AND printStatus = 0' ELSE '' END + '
                    AND exclusionMask & Power(2, DatePart(weekday, GETDATE())-1) = 0
                    AND page_count BETWEEN @p_minPageCount AND ISNULL(@p_maxPageCount, page_count)
                ORDER BY + ' + @defragOrderColumn + ' ' + @defragSortOrder;
     
                SET @getIndexSQL_Param = N'@objectID_Out        INT OUTPUT
                                         , @indexID_Out         INT OUTPUT
                                         , @databaseID_Out      INT OUTPUT
                                         , @databaseName_Out    NVARCHAR(128) OUTPUT
                                         , @fragmentation_Out   INT OUTPUT
                                         , @partitionNumber_Out INT OUTPUT
                                         , @pageCount_Out       INT OUTPUT
                                         , @p_minPageCount      INT
                                         , @p_maxPageCount      INT';
     
                EXECUTE sp_executesql @getIndexSQL
                    , @getIndexSQL_Param
                    , @p_minPageCount       = @minPageCount
                    , @p_maxPageCount       = @maxPageCount
                    , @objectID_Out         = @objectID         OUTPUT
                    , @indexID_Out          = @indexID          OUTPUT
                    , @databaseID_Out       = @databaseID       OUTPUT
                    , @databaseName_Out     = @databaseName     OUTPUT
                    , @fragmentation_Out    = @fragmentation    OUTPUT
                    , @partitionNumber_Out  = @partitionNumber  OUTPUT
                    , @pageCount_Out        = @pageCount        OUTPUT;
     
                IF @debugMode = 1 RAISERROR('  Looking up the specifics for our index...', 0, 42) WITH NOWAIT;
     
                /* Look up index information */
                SELECT @updateSQL = N'UPDATE ids
                    SET schemaName = QUOTENAME(s.name)
                        , objectName = QUOTENAME(o.name)
                        , indexName = QUOTENAME(i.name)
                    FROM dbo.dba_indexDefragStatus AS ids
                    INNER JOIN ' + @databaseName + '.sys.objects AS o
                        ON ids.objectID = o.[object_id]
                    INNER JOIN ' + @databaseName + '.sys.indexes AS i
                        ON o.[object_id] = i.[object_id]
                        AND ids.indexID = i.index_id
                    INNER JOIN ' + @databaseName + '.sys.schemas AS s
                        ON o.schema_id = s.schema_id
                    WHERE o.[object_id] = ' + CAST(@objectID AS VARCHAR(10)) + '
                        AND i.index_id = ' + CAST(@indexID AS VARCHAR(10)) + '
                        AND i.type > 0
                        AND ids.databaseID = ' + CAST(@databaseID AS VARCHAR(10));
     
                EXECUTE sp_executesql @updateSQL;
     
                /* Grab our object names */
                SELECT @objectName  = objectName
                    , @schemaName   = schemaName
                    , @indexName    = indexName
                FROM dbo.dba_indexDefragStatus
                WHERE objectID = @objectID
                    AND indexID = @indexID
                    AND databaseID = @databaseID;
     
                IF @debugMode = 1 RAISERROR('  Grabbing the partition COUNT...', 0, 42) WITH NOWAIT;
     
                /* Determine if the index is partitioned */
                SELECT @partitionSQL = 'SELECT @partitionCount_OUT = COUNT(*)
                                            FROM ' + @databaseName + '.sys.partitions
                                            WHERE object_id = ' + CAST(@objectID AS VARCHAR(10)) + '
                                                AND index_id = ' + CAST(@indexID AS VARCHAR(10)) + ';'
                    , @partitionSQL_Param = '@partitionCount_OUT INT OUTPUT';
     
                EXECUTE sp_executesql @partitionSQL, @partitionSQL_Param, @partitionCount_OUT = @partitionCount OUTPUT;
     
                IF @debugMode = 1 RAISERROR('  Seeing IF there are any LOBs to be handled...', 0, 42) WITH NOWAIT;
     
                /* Determine if the table contains LOBs */
                SELECT @LOB_SQL = ' SELECT @containsLOB_OUT = COUNT(*)
                                    FROM ' + @databaseName + '.sys.columns WITH (NoLock) 
                                    WHERE [object_id] = ' + CAST(@objectID AS VARCHAR(10)) + '
                                       AND (system_type_id IN (34, 35, 99)
                                                OR max_length = -1);'
                                    /*  system_type_id --> 34 = IMAGE, 35 = TEXT, 99 = NTEXT
                                        max_length = -1 --> VARBINARY(MAX), VARCHAR(MAX), NVARCHAR(MAX), XML */
                        , @LOB_SQL_Param = '@containsLOB_OUT INT OUTPUT';
     
                EXECUTE sp_executesql @LOB_SQL, @LOB_SQL_Param, @containsLOB_OUT = @containsLOB OUTPUT;
     
                IF @debugMode = 1 RAISERROR('  Checking for indexes that do NOT allow page locks...', 0, 42) WITH NOWAIT;
     
                /* Determine if page locks are allowed; for those indexes, we need to always REBUILD */
                SELECT @allowPageLockSQL = 'SELECT @allowPageLocks_OUT = COUNT(*)
                                            FROM ' + @databaseName + '.sys.indexes
                                            WHERE object_id = ' + CAST(@objectID AS VARCHAR(10)) + '
                                                AND index_id = ' + CAST(@indexID AS VARCHAR(10)) + '
                                                AND Allow_Page_Locks = 0;'
                    , @allowPageLockSQL_Param = '@allowPageLocks_OUT INT OUTPUT';
     
                EXECUTE sp_executesql @allowPageLockSQL, @allowPageLockSQL_Param, @allowPageLocks_OUT = @allowPageLocks OUTPUT;
     
                IF @debugMode = 1 RAISERROR('  Building our SQL statements...', 0, 42) WITH NOWAIT;
     
                /* IF there's not a lot of fragmentation, or if we have a LOB, we should REORGANIZE */
                IF (@fragmentation < @rebuildThreshold OR @containsLOB >= 1 OR @partitionCount > 1)
                    AND @allowPageLocks = 0
                BEGIN
     
                    SET @sqlCommand = N'ALTER INDEX ' + @indexName + N' ON ' + @databaseName + N'.' 
                                        + @schemaName + N'.' + @objectName + N' REORGANIZE';
     
                    /* If our index is partitioned, we should always REORGANIZE */
                    IF @partitionCount > 1
                        SET @sqlCommand = @sqlCommand + N' PARTITION = ' 
                                        + CAST(@partitionNumber AS NVARCHAR(10));
     
                END
                /* If the index is heavily fragmented and doesn't contain any partitions or LOB's, 
                   or if the index does not allow page locks, REBUILD it */
                ELSE IF (@fragmentation >= @rebuildThreshold OR @allowPageLocks <> 0)
                    AND ISNULL(@containsLOB, 0) != 1 AND @partitionCount <= 1
                BEGIN
     
                    /* Set online REBUILD options; requires Enterprise Edition */
                    IF @onlineRebuild = 1 AND @editionCheck = 1 
                        SET @rebuildCommand = N' REBUILD WITH (ONLINE = ON';
                    ELSE
                        SET @rebuildCommand = N' REBUILD WITH (ONLINE = Off';
     
                    /* Set sort operation preferences */
                    IF @sortInTempDB = 1 
                        SET @rebuildCommand = @rebuildCommand + N', SORT_IN_TEMPDB = ON';
                    ELSE
                        SET @rebuildCommand = @rebuildCommand + N', SORT_IN_TEMPDB = Off';
     
                    /* Set processor restriction options; requires Enterprise Edition */
                    IF @maxDopRestriction IS NOT NULL AND @editionCheck = 1
                        SET @rebuildCommand = @rebuildCommand + N', MAXDOP = ' + CAST(@maxDopRestriction AS VARCHAR(2)) + N')';
                    ELSE
                        SET @rebuildCommand = @rebuildCommand + N')';
     
                    SET @sqlCommand = N'ALTER INDEX ' + @indexName + N' ON ' + @databaseName + N'.'
                                    + @schemaName + N'.' + @objectName + @rebuildCommand;
     
                END
                ELSE
                    /* Print an error message if any indexes happen to not meet the criteria above */
                    IF @printCommands = 1 OR @debugMode = 1
                        RAISERROR('We are unable to defrag this index.', 0, 42) WITH NOWAIT;
     
                /* Are we executing the SQL?  IF so, do it */
                IF @executeSQL = 1
                BEGIN
     
                    SET @debugMessage = 'Executing: ' + @sqlCommand;
     
                    /* Print the commands we're executing if specified to do so */
                    IF @printCommands = 1 OR @debugMode = 1
                        RAISERROR(@debugMessage, 0, 42) WITH NOWAIT;
     
                    /* Grab the time for logging purposes */
                    SET @datetimestart  = GETDATE();
     
                    /* Log our actions */
                    INSERT INTO dbo.dba_indexDefragLog
                    (
                          databaseID
                        , databaseName
                        , objectID
                        , objectName
                        , indexID
                        , indexName
                        , partitionNumber
                        , fragmentation
                        , page_count
                        , DATETIMEStart
                        , sqlStatement
                    )
                    SELECT
                          @databaseID
                        , @databaseName
                        , @objectID
                        , @objectName
                        , @indexID
                        , @indexName
                        , @partitionNumber
                        , @fragmentation
                        , @pageCount
                        , @datetimestart
                        , @sqlCommand;
     
                    SET @indexDefrag_id = SCOPE_IDENTITY();
     
                    /* Wrap our execution attempt in a TRY/CATCH and log any errors that occur */
                    BEGIN TRY
     
                        /* Execute our defrag! */
                        EXECUTE sp_executesql @sqlCommand;
                        SET @dateTimeEnd = GETDATE();
     
                        /* Update our log with our completion time */
                        UPDATE dbo.dba_indexDefragLog
                        SET dateTimeEnd = @dateTimeEnd
                            , durationSeconds = DATEDIFF(second, @datetimestart, @dateTimeEnd)
                        WHERE indexDefrag_id = @indexDefrag_id;
     
                    END TRY
                    BEGIN CATCH
     
                        /* Update our log with our error message */
                        UPDATE dbo.dba_indexDefragLog
                        SET dateTimeEnd = GETDATE()
                            , durationSeconds = -1
                            , errorMessage = ERROR_MESSAGE()
                        WHERE indexDefrag_id = @indexDefrag_id;
     
                        IF @debugMode = 1 
                            RAISERROR('  An error has occurred executing this command! Please review the dba_indexDefragLog table for details.'
                                , 0, 42) WITH NOWAIT;
     
                    END CATCH
     
                    /* Just a little breather for the server */
                    WAITFOR DELAY @defragDelay;
     
                    UPDATE dbo.dba_indexDefragStatus
                    SET defragDate = GETDATE()
                        , printStatus = 1
                    WHERE databaseID       = @databaseID
                      AND objectID         = @objectID
                      AND indexID          = @indexID
                      AND partitionNumber  = @partitionNumber;
     
                END
                ELSE
                /* Looks like we're not executing, just printing the commands */
                BEGIN
                    IF @debugMode = 1 RAISERROR('  Printing SQL statements...', 0, 42) WITH NOWAIT;
     
                    IF @printCommands = 1 OR @debugMode = 1 
                        PRINT ISNULL(@sqlCommand, 'error!');
     
                    UPDATE dbo.dba_indexDefragStatus
                    SET printStatus = 1
                    WHERE databaseID       = @databaseID
                      AND objectID         = @objectID
                      AND indexID          = @indexID
                      AND partitionNumber  = @partitionNumber;
                END
     
            END
     
            /* Do we want to output our fragmentation results? */
            IF @printFragmentation = 1
            BEGIN
     
                IF @debugMode = 1 RAISERROR('  Displaying a summary of our action...', 0, 42) WITH NOWAIT;
     
                SELECT databaseID
                    , databaseName
                    , objectID
                    , objectName
                    , indexID
                    , indexName
                    , partitionNumber
                    , fragmentation
                    , page_count
                    , range_scan_count
                FROM dbo.dba_indexDefragStatus
                WHERE defragDate >= @startdatetime
                ORDER BY defragDate;
     
            END;
     
        END TRY
        BEGIN CATCH
     
            SET @debugMessage = ERROR_MESSAGE() + ' (Line Number: ' + CAST(ERROR_LINE() AS VARCHAR(10)) + ')';
            PRINT @debugMessage;
     
        END CATCH;
     
        /* When everything is said and done, make sure to get rid of our temp table */
        DROP TABLE #databaseList;
        DROP TABLE #processor;
        DROP TABLE #maxPartitionList;
     
        IF @debugMode = 1 RAISERROR('DONE!  Thank you for taking care of your indexes!  :)', 0, 42) WITH NOWAIT;
     
        SET NOCOUNT OFF;
        RETURN 0;
    END
  7. T-SQL Script for Estimating Compression Savings

    A couple of weeks ago, I was working on a Microsoft PDW proof-of-concept (POC) and had to measure compression ratios. In order to do this, I fired up SSMS and wrote a little script. The script will iterate through all tables in a database and run the sp_estimate_data_compression_savings stored procedure. This will only work in SQL Server 2008+ versions running Enterprise edition.

    If you're not familiar with this stored procedure, it basically will tell you what effect PAGE or ROW compression will have on your table/index/partition, etc. There are pro's and con's with compression. What I've tended to see is that compression has very positive results on space, IO, and query duration, with a negative impact on CPU and write speed. Like most things, it's a trade-off and the results will vary by environment, so I recommend you do some testing before you apply compression to all tables. I tend to use compression mostly for my historical tables and partitions and leave my recent data uncompressed. And, back to the script, I use this stored procedure to estimate the impact of compression and to determine whether to use PAGE or ROW compression. PAGE is a higher level of compression, which means it's also more expensive in terms of CPU, so if the difference between the two results is negligible, I'm more apt to just use ROW compression.

    Now that my impromptu compression discussion is done, let's get to the actual script. One final word of caution, however. This is an IO intensive process, so you may want to run it after peak business hours.

    SET NOCOUNT ON;
     
    DECLARE @printOnly  BIT = 0 -- change to 1 if you don't want to execute, just print commands
        , @tableName    VARCHAR(256)
        , @schemaName   VARCHAR(100)
        , @sqlStatement NVARCHAR(1000)
        , @tableCount   INT
        , @statusMsg    VARCHAR(1000);
     
    IF EXISTS(SELECT * FROM tempdb.sys.tables WHERE name LIKE '%#tables%')
        DROP TABLE #tables; 
     
    CREATE TABLE #tables
    (
          database_name     sysname
        , schemaName        sysname NULL
        , tableName         sysname NULL
        , processed         BIT
    );
     
    IF EXISTS(SELECT * FROM tempdb.sys.tables WHERE name LIKE '%#compression%')
        DROP TABLE #compressionResults;
     
    IF NOT EXISTS(SELECT * FROM tempdb.sys.tables WHERE name LIKE '%#compression%')
    BEGIN 
     
        CREATE TABLE #compressionResults
        (
              objectName                    VARCHAR(100)
            , schemaName                    VARCHAR(50)
            , index_id                      INT
            , partition_number              INT
            , size_current_compression      BIGINT
            , size_requested_compression    BIGINT
            , sample_current_compression    BIGINT
            , sample_requested_compression  BIGINT
        );
     
    END;
     
    INSERT INTO #tables
    SELECT DB_NAME()
        , SCHEMA_NAME([schema_id])
        , name
        , 0 -- unprocessed
    FROM sys.tables;
     
    SELECT @tableCount = COUNT(*) FROM #tables;
     
    WHILE EXISTS(SELECT * FROM #tables WHERE processed = 0)
    BEGIN
     
        SELECT TOP 1 @tableName = tableName
            , @schemaName = schemaName
        FROM #tables WHERE processed = 0;
     
        SELECT @statusMsg = 'Working on ' + CAST(((@tableCount - COUNT(*)) + 1) AS VARCHAR(10)) 
            + ' of ' + CAST(@tableCount AS VARCHAR(10))
        FROM #tables
        WHERE processed = 0;
     
        RAISERROR(@statusMsg, 0, 42) WITH NOWAIT;
     
        SET @sqlStatement = 'EXECUTE sp_estimate_data_compression_savings ''' 
                            + @schemaName + ''', ''' + @tableName + ''', NULL, NULL, ''PAGE'';' -- ROW, PAGE, or NONE
     
        IF @printOnly = 1
        BEGIN 
     
            SELECT @sqlStatement;
     
        END
        ELSE
        BEGIN
     
            INSERT INTO #compressionResults
            EXECUTE SP_EXECUTESQL @sqlStatement;
     
        END;
     
        UPDATE #tables
        SET processed = 1
        WHERE tableName = @tableName
            AND schemaName = @schemaName;
     
    END;
     
    SELECT * 
    FROM #compressionResults;
  8. String Parsing Function

    This handy little script parses a string and returns the results as a table. I know there are a ton of string parsing functions out there, but I thought I'd add to the list. ;)

    The basic logic of it (using a CTE) is derived from a forum post I found years ago. The table-valued UDF, delimiter, etc. is all stuff that I added. So thus, while I can not claim complete credit, I still thought it'd be worthwhile to share. Plus this will be used in another script I will be posting soon. :)

    /* Let's create our parsing function... */
    CREATE FUNCTION dbo.dba_parseString_udf
    (
              @stringToParse VARCHAR(8000)  
            , @delimiter     CHAR(1)
    )
    RETURNS @parsedString TABLE (stringValue VARCHAR(128))
    AS
    /*********************************************************************************
        Name:       dba_parseString_udf
     
        Author:     Michelle Ufford, http://sqlfool.com
     
        Purpose:    This function parses string input using a variable delimiter.
     
        Notes:      Two common delimiter values are space (' ') and comma (',')
     
        Date        Initials    Description
        ----------------------------------------------------------------------------
        2011-05-20  MFU         Initial Release
    *********************************************************************************
    Usage: 		
        SELECT *
    	FROM dba_parseString_udf(<string>, <delimiter>);
     
    Test Cases:
     
        1.  multiple strings separated by space
            SELECT * FROM dbo.dba_parseString_udf('  aaa  bbb  ccc ', ' ');
     
        2.  multiple strings separated by comma
            SELECT * FROM dbo.dba_parseString_udf(',aaa,bbb,,,ccc,', ',');
    *********************************************************************************/
    BEGIN
     
        /* Declare variables */
        DECLARE @trimmedString  VARCHAR(8000);
     
        /* We need to trim our string input in case the user entered extra spaces */
        SET @trimmedString = LTRIM(RTRIM(@stringToParse));
     
        /* Let's create a recursive CTE to break down our string for us */
        WITH parseCTE (StartPos, EndPos)
        AS
        (
            SELECT 1 AS StartPos
                , CHARINDEX(@delimiter, @trimmedString + @delimiter) AS EndPos
            UNION ALL
            SELECT EndPos + 1 AS StartPos
                , CHARINDEX(@delimiter, @trimmedString + @delimiter , EndPos + 1) AS EndPos
            FROM parseCTE
            WHERE CHARINDEX(@delimiter, @trimmedString + @delimiter, EndPos + 1) <> 0
        )
     
        /* Let's take the results and stick it in a table */  
        INSERT INTO @parsedString
        SELECT SUBSTRING(@trimmedString, StartPos, EndPos - StartPos)
        FROM parseCTE
        WHERE LEN(LTRIM(RTRIM(SUBSTRING(@trimmedString, StartPos, EndPos - StartPos)))) > 0
        OPTION (MaxRecursion 8000);
     
        RETURN;   
    END
  9. 11-Word Warning

    Tom LaRock posted a new Meme Monday challenge: "Write a SQL blog post in 11 words or less."

    Donabel Santos tagged me, and I couldn't resist the challenge. So here's my entry:

    Hasty coding, error prone. No backups, data loss. Company for sale.

    This was inspired by the recent spate of stories I've heard about companies that have failed because they did not properly manage their data and databases.

    I don't know who's been tagged or not, so I'm gagging some of my SQL Saturday Chicago friends:

  10. DAMSQL

    After much consideration, I am leaving the SQL Server world. Yes, I realize that SQL Server serves as the cornerstone to many well-paying, stimulating, and fulfilling careers. And yes, I realize that SQL Server has arguably the best technical community in the world. But that's the problem. SQL Server is too easy. I want more of a challenge. I want something that I need to fight with to make it work. And for that reason, from this point forward, I will devote all of my time, energy, and money to furthering the goals of PostgreSQL.

    I will also be founding a new not-for-profit group, Developers Against Microsoft SQL Server... or DAMSQL for short. I have purchased a bunker in Utah to serve as the headquarters for DAMSQL. All are welcome to join the group, but you must first pass 3 trials. Step 1 is to renounce your love for any database other than the one true database, Postgres. Step 2 is to quit your job and leave your families, but not before wiring all of your savings to a bank account in the Cayman Islands. And Step 3 involves a trek through the wilderness under a full moon, wearing nothing but your underwear and a blindfold. There's more to Step 3, but I don't want to give too much away.

    Long live open source!

    While I hope it's rather obvious, yes, this is an April Fool's Day post. I still totally

    For those of you not familiar with April Fool's Day, the first day of April is often celebrated by pulling good-natured pranks or trying to "fool" others. I don't have any issues with Postgres, but thought it would be a good source of humor for my friends who know how dedicated I am to the SQL Server platform. This is a fictional post. No offense is intended, and any similarities to real database cult groups is unintentional.

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