The document contains SQL scripts that: 1. Perform various diagnostic checks on indexes such as retrieving index status, enabling/disabling tracing, and viewing index usage statistics. 2. Create tables with different indexing configurations like no indexes, non-clustered indexes, and clustered indexes to test query performance. 3. Query system catalog views and dynamic management functions to retrieve detailed metadata about indexes including column definitions, storage details, usage statistics, and unused indexes.

1. --DBCC TRACESTATUS(-1);
--GO
--DBCC TRACESTATUS (2528, 3205);
--GO
--DBCC TRACESTATUS (3205, -1);
--GO
--DBCC TRACESTATUS();
--GO
--DBCC TRACESTATUS(-1);
--DBCC TRACEOFF(8602, 8755, 8722)
--DBCC TRACEON(8602, 8755, 8722)
--DBCC TRACEON(8602)
--select * from Wiz_00004.dbo.LARData with (INDEX = 2)
USE [General]
GO
-- List all heap tables
SELECT SCH.name + '.' + TBL.name AS TableName
FROM sys.tables AS TBL
INNER JOIN sys.schemas AS SCH
ON TBL.schema_id = SCH.schema_id
INNER JOIN sys.indexes AS IDX
ON TBL.object_id = IDX.object_id
AND IDX.type = 0 -- = Heap
ORDER BY TableName
--drop table GenderNG
--1 - Table with no indexes
if OBJECT_ID('GenderNG') is NOT null drop table GenderNG
select IDENTITY(int,1,1) as RowNumb,* INTO GenderNG from
General.dbo.Gender
print 'Getting heap table scan'
select * from GenderNG where gendername='YOSHIE'
GO
--2- Table with non-clustered index on gendername column
IF EXISTS (SELECT * FROM sys.indexes WHERE object_id =
OBJECT_ID(N'[dbo].[GenderNG]') AND name = N'nc_gendername')

2. DROP INDEX [nc_gendername] ON [dbo].[GenderNG] WITH ( ONLINE = OFF )
GO
CREATE NONCLUSTERED INDEX [nc_gendername] ON [dbo].[GenderNG]
(
[gendername] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB
= OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
print 'Getting index seek & heap table lookup'
select * from GenderNG where gendername='YOSHIE'
--3- Table with clustered index on gendername column
IF EXISTS (SELECT * FROM sys.indexes WHERE object_id =
OBJECT_ID(N'[dbo].[GenderNG]') AND name = N'cl_gendername')
DROP INDEX [cl_gendername] ON [dbo].[GenderNG] WITH ( ONLINE = OFF )
GO
CREATE CLUSTERED INDEX [cl_gendername] ON [dbo].[GenderNG]
(
[gendername] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB
= OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
select * from GenderNG where gendername='YOSHIE'
GO
GO
--4- Table with clustered index on rownumb and non-clustered on
gendername column
--dropping previous CL IDX
IF EXISTS (SELECT * FROM sys.indexes WHERE object_id =
OBJECT_ID(N'[dbo].[GenderNG]') AND name = N'cl_gendername')
DROP INDEX [cl_gendername] ON [dbo].[GenderNG] WITH ( ONLINE = OFF )
GO
IF EXISTS (SELECT * FROM sys.indexes WHERE object_id =
OBJECT_ID(N'[dbo].[GenderNG]') AND name = N'cl_rownumb')
DROP INDEX [cl_rownumb] ON [dbo].[GenderNG] WITH ( ONLINE = OFF )
GO
CREATE CLUSTERED INDEX [cl_rownumb] ON [dbo].[GenderNG]

3. (
[rownumb] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB
= OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON ) ON [PRIMARY]
GO
select * from GenderNG where gendername='YOSHIE'
--Fill Factor
exec sp_spaceused 'dbo.GenderNG'
IF EXISTS (SELECT * FROM sys.indexes WHERE object_id =
OBJECT_ID(N'[dbo].[GenderNG]') AND name = N'nc_gendername')
DROP INDEX [nc_gendername] ON [dbo].[GenderNG] WITH ( ONLINE = OFF )
GO
CREATE NONCLUSTERED INDEX [nc_gendername] ON [dbo].[GenderNG]
(
[gendername] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB
= OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 50) ON
[PRIMARY]
GO
print 'Approximatly twice the size of the index created earlier'
exec sp_spaceused 'dbo.GenderNG'
GO
--This function gives you information about insert, update and delete
operations that occur on a particular index
SELECT OBJECT_NAME(A.[OBJECT_ID]) AS [OBJECT NAME],
I.[NAME] AS [INDEX NAME],
A.LEAF_INSERT_COUNT,
A.LEAF_UPDATE_COUNT,
A.LEAF_DELETE_COUNT
FROM SYS.DM_DB_INDEX_OPERATIONAL_STATS (NULL,NULL,NULL,NULL ) A
INNER JOIN SYS.INDEXES AS I
ON I.[OBJECT_ID] = A.[OBJECT_ID]
AND I.INDEX_ID = A.INDEX_ID
WHERE OBJECTPROPERTY(A.[OBJECT_ID],'IsUserTable') = 1
GO
--This view gives you information about overall access methods to your
indexes.
SELECT OBJECT_NAME(S.[OBJECT_ID]) AS [OBJECT NAME],
I.[NAME] AS [INDEX NAME],
USER_SEEKS,
USER_SCANS,

4. USER_LOOKUPS,
USER_UPDATES
FROM SYS.DM_DB_INDEX_USAGE_STATS AS S
INNER JOIN SYS.INDEXES AS I
ON I.[OBJECT_ID] = S.[OBJECT_ID]
AND I.INDEX_ID = S.INDEX_ID
WHERE OBJECTPROPERTY(S.[OBJECT_ID],'IsUserTable') = 1
--we are just using sys.dm_db_index_usage_stats and sys.objects to get
a list of the indexes that have been used and how they are being used.
SELECT DB_NAME(DATABASE_ID) AS DATABASENAME,
OBJECT_NAME(B.OBJECT_ID) AS TABLENAME,
INDEX_NAME = (SELECT NAME
FROM SYS.INDEXES A
WHERE A.OBJECT_ID = B.OBJECT_ID
AND A.INDEX_ID = B.INDEX_ID),
USER_SEEKS,
USER_SCANS,
USER_LOOKUPS,
USER_UPDATES
FROM SYS.DM_DB_INDEX_USAGE_STATS B
INNER JOIN SYS.OBJECTS C
ON B.OBJECT_ID = C.OBJECT_ID
WHERE DATABASE_ID = DB_ID(DB_NAME())
AND C.TYPE <> 'S'
--we are listing each user table and all of the tables indexes that
have not been used by using a NOT EXISTS against
sys.dm_db_index_usage_stats.
SELECT DB_NAME() AS DATABASENAME,
OBJECT_NAME(B.OBJECT_ID) AS TABLENAME,
B.NAME AS INDEXNAME,
B.INDEX_ID
FROM SYS.OBJECTS A
INNER JOIN SYS.INDEXES B
ON A.OBJECT_ID = B.OBJECT_ID
WHERE NOT EXISTS (SELECT *
FROM SYS.DM_DB_INDEX_USAGE_STATS C
WHERE B.OBJECT_ID = C.OBJECT_ID
AND B.INDEX_ID = C.INDEX_ID)
AND A.TYPE <> 'S'
ORDER BY 1, 2, 3
--In this query we are listing each user table, all of its indexes and
the columns that make up the index.
SELECT A.NAME,
B.NAME,
C.KEY_ORDINAL,
D.NAME

5. FROM SYS.OBJECTS A
INNER JOIN SYS.INDEXES B
ON A.OBJECT_ID = B.OBJECT_ID
INNER JOIN SYS.INDEX_COLUMNS C
ON B.OBJECT_ID = C.OBJECT_ID
AND B.INDEX_ID = C.INDEX_ID
INNER JOIN SYS.COLUMNS D
ON C.OBJECT_ID = D.OBJECT_ID
AND C.COLUMN_ID = D.COLUMN_ID
WHERE A.TYPE <> 'S'
ORDER BY 1, 2, 3
--Covering Index Information
SELECT
SCHEMA_NAME([sObj].[schema_id]) AS [SchemaName]
, [sObj].[name] AS [ObjectName]
, CASE
WHEN [sObj].[type] = 'U' THEN 'Table'
WHEN [sObj].[type] = 'V' THEN 'View'
END AS [ObjectType]
, [sIdx].[index_id] AS [IndexID] -- 0: Heap; 1: Clustered Idx; >
1: Nonclustered Idx;
, ISNULL([sIdx].[name], 'N/A') AS [IndexName]
, CASE
WHEN [sIdx].[type] = 0 THEN 'Heap'
WHEN [sIdx].[type] = 1 THEN 'Clustered'
WHEN [sIdx].[type] = 2 THEN 'Nonclustered'
WHEN [sIdx].[type] = 3 THEN 'XML'
WHEN [sIdx].[type] = 4 THEN 'Spatial'
WHEN [sIdx].[type] = 5 THEN 'Reserved for future use'
WHEN [sIdx].[type] = 6 THEN 'Nonclustered columnstore index'
END AS [IndexType]
, [sCol].[name] AS [ColumnName]
, CASE
WHEN [sIdxCol].[is_included_column] = 0x1 THEN 'Yes'
WHEN [sIdxCol].[is_included_column] = 0x0 THEN 'No'
WHEN [sIdxCol].[is_included_column] IS NULL THEN 'N/A'
END AS [IsIncludedColumn]
, [sIdxCol].[key_ordinal] AS [KeyOrdinal]
FROM
[sys].[indexes] AS [sIdx]
INNER JOIN [sys].[objects] AS [sObj]
ON [sIdx].[object_id] = [sObj].[object_id]
LEFT JOIN [sys].[index_columns] AS [sIdxCol]
ON [sIdx].[object_id] = [sIdxCol].[object_id]
AND [sIdx].[index_id] = [sIdxCol].[index_id]
LEFT JOIN [sys].[columns] AS [sCol]
ON [sIdxCol].[object_id] = [sCol].[object_id]
AND [sIdxCol].[column_id] = [sCol].[column_id]
WHERE
SCHEMA_NAME([sObj].[schema_id]) = 'Production'

6. AND [sObj].[name] = 'ProductReview'
AND [sIdx].[name] = 'IX_ProductReview_ProductID_Name'
--query the physical statistics of an index like Size, Percentage
Fragmentation etc
SELECT
@@SERVERNAME AS [ServerName]
, DB_NAME() AS [DatabaseName]
, SCHEMA_NAME([sObj].[schema_id]) AS [SchemaName]
, [sObj].[name] AS [ObjectName]
, CASE
WHEN [sObj].[type] = 'U' THEN 'Table'
WHEN [sObj].[type] = 'V' THEN 'View'
END AS [ObjectType]
, [sIdx].[index_id] AS [IndexID]
, ISNULL([sIdx].[name], 'N/A') AS [IndexName]
, CASE
WHEN [sIdx].[type] = 0 THEN 'Heap'
WHEN [sIdx].[type] = 1 THEN 'Clustered'
WHEN [sIdx].[type] = 2 THEN 'Nonclustered'
WHEN [sIdx].[type] = 3 THEN 'XML'
WHEN [sIdx].[type] = 4 THEN 'Spatial'
WHEN [sIdx].[type] = 5 THEN 'Reserved for future use'
WHEN [sIdx].[type] = 6 THEN 'Nonclustered columnstore index'
END AS [IndexType]
, ISNULL([sPtn].[partition_number], 1) AS [PartitionNumber]
, [sdmfIPS].[alloc_unit_type_desc] AS [IndexAllocationUnitType]
, [IdxSizeDetails].[IndexSizeInKB]
, [sIdx].[fill_factor] AS [FillFactor]
, CAST([sdmfIPS].[avg_fragmentation_in_percent] AS NUMERIC(5,2)) AS
[AvgPctFrag]
FROM
[sys].[indexes] AS [sIdx]
INNER JOIN [sys].[objects] AS [sObj]
ON [sIdx].[object_id] = [sObj].[object_id]
LEFT JOIN [sys].[partitions] AS [sPtn]
ON [sIdx].[object_id] = [sPtn].[object_id]
AND [sIdx].[index_id] = [sPtn].[index_id]
LEFT JOIN (
SELECT
[sIdx].[object_id]
, [sIdx].[index_id]
, SUM([sAU].[used_pages]) * 8 AS [IndexSizeInKB]
FROM
[sys].[indexes] AS [sIdx]
INNER JOIN [sys].[partitions] AS [sPtn]
ON [sIdx].[object_id] = [sPtn].[object_id]
AND [sIdx].[index_id] = [sPtn].[index_id]
INNER JOIN [sys].[allocation_units] AS [sAU]
ON [sPtn].[partition_id] = [sAU].[container_id]
GROUP BY [sIdx].[object_id], [sIdx].[index_id]

7. ) [IdxSizeDetails]
ON [sIdx].[object_id] = [IdxSizeDetails].[object_id]
AND [sIdx].[index_id] = [IdxSizeDetails].[index_id]
LEFT JOIN [sys].[dm_db_index_physical_stats]
(DB_ID(),NULL,NULL,NULL,'LIMITED') [sdmfIPS]
ON [sIdx].[object_id] = [sdmfIPS].[object_id]
AND [sIdx].[index_id] = [sdmfIPS].[index_id]
AND [sdmfIPS].[database_id] = DB_ID()
WHERE
[sObj].[type] IN ('U','V') -- Look in Tables & Views
AND [sObj].[is_ms_shipped] = 0x0 -- Exclude System Generated
Objects
AND [sIdx].[is_disabled] = 0x0 -- Exclude Disabled Indexes
-- understanding how effectively the existing indexes are being used.
SELECT
@@SERVERNAME AS [ServerName]
, DB_NAME() AS [DatabaseName]
, SCHEMA_NAME([sObj].[schema_id]) AS [SchemaName]
, [sObj].[name] AS [ObjectName]
, CASE
WHEN [sObj].[type] = 'U' THEN 'Table'
WHEN [sObj].[type] = 'V' THEN 'View'
END AS [ObjectType]
, [sIdx].[index_id] AS [IndexID]
, ISNULL([sIdx].[name], 'N/A') AS [IndexName]
, CASE
WHEN [sIdx].[type] = 0 THEN 'Heap'
WHEN [sIdx].[type] = 1 THEN 'Clustered'
WHEN [sIdx].[type] = 2 THEN 'Nonclustered'
WHEN [sIdx].[type] = 3 THEN 'XML'
WHEN [sIdx].[type] = 4 THEN 'Spatial'
WHEN [sIdx].[type] = 5 THEN 'Reserved for future use'
WHEN [sIdx].[type] = 6 THEN 'Nonclustered columnstore index'
END AS [IndexType]
, [sdmvIUS].[user_seeks] AS [TotalUserSeeks]
, [sdmvIUS].[user_scans] AS [TotalUserScans]
, [sdmvIUS].[user_lookups] AS [TotalUserLookups]
, [sdmvIUS].[user_updates] AS [TotalUserUpdates]
, [sdmvIUS].[last_user_seek] AS [LastUserSeek]
, [sdmvIUS].[last_user_scan] AS [LastUserScan]
, [sdmvIUS].[last_user_lookup] AS [LastUserLookup]
, [sdmvIUS].[last_user_update] AS [LastUserUpdate]
, [sdmfIOPS].[leaf_insert_count] AS [LeafLevelInsertCount]
, [sdmfIOPS].[leaf_update_count] AS [LeafLevelUpdateCount]
, [sdmfIOPS].[leaf_delete_count] AS [LeafLevelDeleteCount]
FROM
[sys].[indexes] AS [sIdx]
INNER JOIN [sys].[objects] AS [sObj]
ON [sIdx].[object_id] = [sObj].[object_id]
LEFT JOIN [sys].[dm_db_index_usage_stats] AS [sdmvIUS]

8. ON [sIdx].[object_id] = [sdmvIUS].[object_id]
AND [sIdx].[index_id] = [sdmvIUS].[index_id]
AND [sdmvIUS].[database_id] = DB_ID()
LEFT JOIN [sys].[dm_db_index_operational_stats]
(DB_ID(),NULL,NULL,NULL) AS [sdmfIOPS]
ON [sIdx].[object_id] = [sdmfIOPS].[object_id]
AND [sIdx].[index_id] = [sdmfIOPS].[index_id]
WHERE
[sObj].[type] IN ('U','V') -- Look in Tables & Views
AND [sObj].[is_ms_shipped] = 0x0 -- Exclude System Generated
Objects
AND [sIdx].[is_disabled] = 0x0 -- Exclude Disabled Indexes
-- unused indexes.
SELECT
@@SERVERNAME AS [ServerName]
, DB_NAME() AS [DatabaseName]
, SCHEMA_NAME([sObj].[schema_id]) AS [SchemaName]
, [sObj].[name] AS [ObjectName]
, CASE
WHEN [sObj].[type] = 'U' THEN 'Table'
WHEN [sObj].[type] = 'V' THEN 'View'
END AS [ObjectType]
, [sIdx].[index_id] AS [IndexID]
, ISNULL([sIdx].[name], 'N/A') AS [IndexName]
, CASE
WHEN [sIdx].[type] = 0 THEN 'Heap'
WHEN [sIdx].[type] = 1 THEN 'Clustered'
WHEN [sIdx].[type] = 2 THEN 'Nonclustered'
WHEN [sIdx].[type] = 3 THEN 'XML'
WHEN [sIdx].[type] = 4 THEN 'Spatial'
WHEN [sIdx].[type] = 5 THEN 'Reserved for future use'
WHEN [sIdx].[type] = 6 THEN 'Nonclustered columnstore index'
END AS [IndexType]
FROM
[sys].[indexes] AS [sIdx]
INNER JOIN [sys].[objects] AS [sObj]
ON [sIdx].[object_id] = [sObj].[object_id]
WHERE
NOT EXISTS (
SELECT *
FROM [sys].[dm_db_index_usage_stats] AS [sdmfIUS]
WHERE
[sIdx].[object_id] = [sdmfIUS].[object_id]
AND [sIdx].[index_id] = [sdmfIUS].[index_id]
AND [sdmfIUS].[database_id] = DB_ID()
)
AND [sObj].[type] IN ('U','V') -- Look in Tables & Views
AND [sObj].[is_ms_shipped] = 0x0 -- Exclude System Generated
Objects
AND [sIdx].[is_disabled] = 0x0 -- Exclude Disabled Indexes

9. -- missing index
SELECT
@@SERVERNAME AS [ServerName]
, DB_NAME() AS [DatabaseName]
, SCHEMA_NAME([sObj].[schema_id]) AS [SchemaName]
, [sObj].[name] AS [ObjectName]
, CASE [sObj].[type]
WHEN 'U' THEN 'Table'
WHEN 'V' THEN 'View'
ELSE 'Unknown'
END AS [ObjectType]
, [sdmvMID].[equality_columns] AS [EqualityColumns]
, [sdmvMID].[inequality_columns] AS [InequalityColumns]
, [sdmvMID].[included_columns] AS [IncludedColumns]
, [sdmvMIGS].[user_seeks] AS [ExpectedIndexSeeksByUserQueries]
, [sdmvMIGS].[user_scans] AS [ExpectedIndexScansByUserQueries]
, [sdmvMIGS].[last_user_seek] AS
[ExpectedLastIndexSeekByUserQueries]
, [sdmvMIGS].[last_user_scan] AS
[ExpectedLastIndexScanByUserQueries]
, [sdmvMIGS].[avg_total_user_cost] AS
[ExpectedAvgUserQueriesCostReduction]
, [sdmvMIGS].[avg_user_impact] AS
[ExpectedAvgUserQueriesBenefitPct]
FROM
[sys].[dm_db_missing_index_details] AS [sdmvMID]
LEFT JOIN [sys].[dm_db_missing_index_groups] AS [sdmvMIG]
ON [sdmvMID].[index_handle] = [sdmvMIG].[index_handle]
LEFT JOIN [sys].[dm_db_missing_index_group_stats] AS [sdmvMIGS]
ON [sdmvMIG].[index_group_handle] = [sdmvMIGS].[group_handle]
INNER JOIN [sys].[objects] AS [sObj]
ON [sdmvMID].[object_id] = [sObj].[object_id]
WHERE
[sdmvMID].[database_id] = DB_ID() -- Look in the Current Database
AND [sObj].[type] IN ('U','V') -- Look in Tables & Views
AND [sObj].[is_ms_shipped] = 0x0 -- Exclude System Generated
Objects