Skip to content

Instantly share code, notes, and snippets.

@brovish
Created June 13, 2022 08:49
Show Gist options
  • Select an option

  • Save brovish/36292e35cd58bec537f1f717f3c647b4 to your computer and use it in GitHub Desktop.

Select an option

Save brovish/36292e35cd58bec537f1f717f3c647b4 to your computer and use it in GitHub Desktop.
Index Defragmantion Script Template from Expert Performance Indexing in SQL Server
--Listing 9-27. Index Defragmantion Script Template
DECLARE @MaxFragmentation TINYINT=30
,@MinimumPages SMALLINT=1000
,@SQL nvarchar(max)
,@ObjectName NVARCHAR(300)
,@IndexName NVARCHAR(300)
,@CurrentFragmentation DECIMAL(9, 6)
DECLARE @FragmentationState TABLE
(
SchemaName SYSNAME
,TableName SYSNAME
,object_id INT
,IndexName SYSNAME
,index_id INT
,page_count BIGINT
,avg_fragmentation_in_percent FLOAT
,avg_page_space_used_in_percent FLOAT
,type_desc VARCHAR(255)
)
INSERT INTO @FragmentationState
--Listing 9-28. Script to Collect Fragmenation Data
SELECT
s.name as SchemaName
,t.name as TableName
,t.object_id
,i.name as IndexName
,i.index_id
,x.page_count
,x.avg_fragmentation_in_percent
,x.avg_page_space_used_in_percent
,i.type_desc
FROM sys.dm_db_index_physical_stats(db_id(), NULL, NULL, NULL, 'SAMPLED') x
INNER JOIN sys.tables t ON x.object_id = t.object_id
INNER JOIN sys.schemas s ON t.schema_id = s.schema_id
INNER JOIN sys.indexes i ON x.object_id = i.object_id AND x.index_id = i.index_id
WHERE x.index_id > 0
AND alloc_unit_type_desc = 'IN_ROW_DATA'
DECLARE INDEX_CURSE CURSOR LOCAL FAST_FORWARD FOR
--Listing 9-29. Script to Identify Fragmented Indexes
SELECT QUOTENAME(x.SchemaName)+'.'+QUOTENAME(x.TableName)
,CASE WHEN x.type_desc = 'CLUSTERED' THEN 'ALL'
ELSE QUOTENAME(x.IndexName) END
,x.avg_fragmentation_in_percent
FROM @FragmentationState x
LEFT OUTER JOIN @FragmentationState y ON x.object_id = y.object_id AND y.index_id = 1
WHERE (
x.type_desc = 'CLUSTERED'
AND y.type_desc = 'CLUSTERED'
)
OR y.index_id IS NULL
ORDER BY x.object_id
,x.index_id
OPEN INDEX_CURSE
WHILE 1=1
BEGIN
FETCH NEXT FROM INDEX_CURSE INTO @ObjectName, @IndexName
,@CurrentFragmentation
IF @@FETCH_STATUS <> 0
BREAK
--Listing 9-30. Script to Build Index Defragmentation Statements
SELECT @SQL='ALTER INDEX '
+@IndexName+' ON '+@ObjectName
+CASE WHEN @CurrentFragmentation <= 30
THEN ' REORGANIZE;'
ELSE ' REBUILD'
+CASE WHEN CONVERT(VARCHAR(100), SERVERPROPERTY('Edition')) LIKE 'Data Center%'
OR CONVERT(VARCHAR(100), SERVERPROPERTY('Edition')) LIKE 'Enterprise%'
OR CONVERT(VARCHAR(100), SERVERPROPERTY('Edition')) LIKE 'Developer%'
THEN ' WITH (ONLINE=ON, SORT_IN_TEMPDB=ON) '
END+';'
END
RAISERROR (@SQL, 10, 1) WITH NOWAIT;
EXEC sp_ExecuteSQL @SQL
END
CLOSE INDEX_CURSE
DEALLOCATE INDEX_CURSE
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment