SQL Server Script – Defragment All Indexes

SQL Server

Sometimes you just want to run a simple script to defragment all indexes in your database. That is usually fairly easy, and there are even entire projects written to make this easy to schedule. If you just need a simple one-time script to just defragment all the indexes in your database that are fragmented above a specific percentage, this script might be your best solution.

/* Originally created by Microsoft */
/* Error corrected by Pinal Dave   */
-- Specify your Database Name
USE AdventureWorks;
GO
-- Declare variables
SET NOCOUNT ON;
DECLARE @tablename VARCHAR(128);
DECLARE @execstr VARCHAR(255);
DECLARE @objectid INT;
DECLARE @indexid INT;
DECLARE @frag decimal;
DECLARE @maxfrag decimal;
-- Decide on the maximum fragmentation to allow for.
SELECT @maxfrag = 30.0;
-- Declare a cursor.
DECLARE tables CURSOR FOR
SELECT CAST(TABLE_SCHEMA AS VARCHAR(100))
+'.'+CAST(TABLE_NAME AS VARCHAR(100))
AS Table_Name
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE';
-- Create the table.
CREATE TABLE #fraglist (
     ObjectName CHAR(255),
     ObjectId INT,
     IndexName CHAR(255),
     IndexId INT,
     Lvl INT,
     CountPages INT,
     CountRows INT,
     MinRecSize INT,
     MaxRecSize INT,
     AvgRecSize INT,
     ForRecCount INT,
     Extents INT,
     ExtentSwitches INT,
     AvgFreeBytes INT,
     AvgPageDensity INT,
     ScanDensity decimal,
     BestCount INT,
     ActualCount INT,
     LogicalFrag decimal,
     ExtentFrag decimal
);
-- Open the cursor.
OPEN tables;
-- Loop through all the tables in the database.
FETCH NEXT
FROM tables
INTO @tablename;
WHILE @@FETCH_STATUS = 0
BEGIN;
     -- Do the showcontig of all indexes of the table
     INSERT INTO #fraglist
     EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''')
     WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS');
     FETCH NEXT
     FROM tables
     INTO @tablename;
END;
-- Close and deallocate the cursor.
CLOSE tables;
DEALLOCATE tables;
-- Declare the cursor for the list of indexes to be defragged.
DECLARE indexes CURSOR FOR
SELECT ObjectName, ObjectId, IndexId, LogicalFrag
FROM #fraglist
WHERE LogicalFrag >= @maxfrag
AND INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0;
-- Open the cursor.
OPEN indexes;
-- Loop through the indexes.
FETCH NEXT
FROM indexes
INTO @tablename, @objectid, @indexid, @frag;
WHILE @@FETCH_STATUS = 0
BEGIN;
     PRINT 'Executing DBCC INDEXDEFRAG (0, ' + RTRIM(@tablename) + ',
     ' + RTRIM(@indexid) + ') - fragmentation currently '
     + RTRIM(CONVERT(VARCHAR(15),@frag)) + '%';
     SELECT @execstr = 'DBCC INDEXDEFRAG (0, ' + RTRIM(@objectid) + ',
     ' + RTRIM(@indexid) + ')';
     EXEC (@execstr);
     FETCH NEXT
     FROM indexes
     INTO @tablename, @objectid, @indexid, @frag;
END;
-- Close and deallocate the cursor.
CLOSE indexes;
DEALLOCATE indexes;
-- Delete the temporary table.
DROP TABLE #fraglist;
GO

To read the entire post by Pinal Dave, you can go here.

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