Table Information including Index information (Usage, Blocks and Reads)

Article
08/25/2009

The query below combines these three queries into one:
Index Usage Query
Recent Bocking History
Table Information Query

It can be used to just see the number of records in each table. But also by just changing "ORDER BY", it can be used to see which index cause most blocking / wait time / updates or locks. Or to compare Index Updates with Index Reads to get an idea of cost versus benefit for each index for the purpose of index tuning.

So in short, one query gives you:
- Index / Table Information
- Index usage (benefits and costs information for each index)
- Index locks, blocks, wait time and updates per read (cost/benefit).

The query must be run in your NAV database. It will create a table called z_IUQ2_Temp_Index_Keys and use various Dynamic Management Views to collect information for each index into this table. First time you run it, or if you want to refresh data, you must run the whole query which may take up to a minute of two for each company in the database. After that if you just want to change sorting / get the results again, then you only need to run the last part of the query, beginning with:

-- Select results

The last lines suggest various "ORDER BY"s that might be useful to enable instead of the default one, which is by Table Name.

Lars Lohndorf-Larsen

Microsoft Dynamics UK

Microsoft Customer Service and Support (CSS) EMEA

These postings are provided "AS IS" with no warranties and confer no rights. You assume all risk for your use.

--use NavisionDatabase

OBJECT_ID ('z_IUQ2_Temp_Index_Keys', 'U') IS NOT NULL

DROP

TABLE z_IUQ2_Temp_Index_Keys;

-- Generate list of indexes with key list

create

table z_IUQ2_Temp_Index_Keys(

[l1] [int]

NOT NULL,

[F_Obj_ID] [int]

NOT NULL,

[F_Schema_Name] [nvarchar]

(128) NULL,

[F_Table_Name] [nvarchar]

(128) NOT NULL,

[F_Row_Count] [int]

NULL,

[F_Reserved] [int]

NULL,

[F_Data] [int]

NULL,

[F_Index_Size] [int]

NULL,

[F_UnUsed] [int]

NULL,

[F_Index_Name] [nvarchar]

(128) NOT NULL,

[F_Index_ID] [int]

NOT NULL,

[F_Column_Name] [nvarchar]

(128) NOT NULL,

[F_User_Updates] [int]

NULL,

[F_User_Reads] [int]

NULL,

[F_Locks] [int]

NULL,

[F_Blocks] [int]

NULL,

[F_Block_Wait_Time] [int]

NULL,

[F_Last_Used] [datetime]

NULL,

[F_Index_Type] [nvarchar]

(128) NOT NULL,

[F_Index_Column_ID] [int]

NOT NULL,

[F_Last_Seek] [datetime]

NULL,

[F_Last_Scan] [datetime]

NULL,

[F_Last_Lookup] [datetime]

NULL,

[Index_Key_List] [nvarchar]

(MAX) NULL

)

CREATE

NONCLUSTERED INDEX [Object_ID_Index] ON [dbo].[z_IUQ2_Temp_Index_Keys]

(

[F_Obj_ID] ASC

)

CREATE

NONCLUSTERED INDEX [Index_ID_Index] ON [dbo].[z_IUQ2_Temp_Index_Keys]

(

[F_Index_ID] ASC

)

CREATE

NONCLUSTERED INDEX [RowCount_ID_Index] ON [dbo].[z_IUQ2_Temp_Index_Keys]

(

[F_Row_Count] ASC

)

insert

into

z_IUQ2_Temp_Index_Keys

SELECT

(

row_number() over(order by a3.name, a2.name))%2 as l1,

.object_id,

.name AS [schemaname],

.name AS [tablename],

.rows as row_count,

(

a1.reserved + ISNULL(a4.reserved,0))* 8 AS reserved,

.data * 8 AS data,

(

CASE WHEN (a1.used + ISNULL(a4.used,0)) > a1.data THEN (a1.used + ISNULL(a4.used,0)) - a1.data ELSE 0 END) * 8 AS index_size,

(

CASE WHEN (a1.reserved + ISNULL(a4.reserved,0)) > a1.used THEN (a1.reserved + ISNULL(a4.reserved,0)) - a1.used ELSE 0 END) * 8 AS unused,

-- Index Description

.name,

.Index_ID,

index_col

(object_name(SIC.object_id),SIC.index_id,SIC.Index_Column_ID),

-- Index Stats

.user_updates,

.user_seeks + US.user_scans + US.user_lookups User_Reads,

-- Index blocks

IStats

.row_lock_count + IStats.page_lock_count ,

IStats

.row_lock_wait_count + IStats.page_lock_wait_count,

IStats

.row_lock_wait_in_ms + IStats.page_lock_wait_in_ms,

-- Dates

case

when

(ISNULL(US.last_user_seek,'00:00:00.000') >= ISNULL(US.last_user_scan,'00:00:00.000')) and (ISNULL(US.last_user_seek,'00:00:00.000') >= ISNULL(US.last_user_lookup,'00:00:00.000')) then US.last_user_seek

when

(ISNULL(US.last_user_scan,'00:00:00.000') >= ISNULL(US.last_user_seek,'00:00:00.000')) and (ISNULL(US.last_user_scan,'00:00:00.000') >= ISNULL(US.last_user_lookup,'00:00:00.000')) then US.last_user_scan

else

US.last_user_lookup

end

as Last_Used_For_Reads,

.type_desc,

SIC

.index_column_id,

.last_user_seek,

.last_user_scan,

.last_user_lookup,

FROM

(

SELECT

.object_id,

SUM

(

CASE

WHEN

(ps.index_id < 2) THEN row_count

ELSE

END

)

AS [rows],

SUM

(ps.reserved_page_count) AS reserved,

SUM

(

CASE

WHEN

(ps.index_id < 2) THEN (ps.in_row_data_page_count + ps.lob_used_page_count + ps.row_overflow_used_page_count)

ELSE

(ps.lob_used_page_count + ps.row_overflow_used_page_count)

END

)

AS data,

SUM

(ps.used_page_count) AS used

FROM

sys.dm_db_partition_stats ps

GROUP

BY ps.object_id) AS a1

LEFT

OUTER JOIN

(

SELECT

.parent_id,

SUM

(ps.reserved_page_count) AS reserved,

SUM

(ps.used_page_count) AS used

FROM

sys.dm_db_partition_stats ps

INNER

JOIN sys.internal_tables it ON (it.object_id = ps.object_id)

WHERE

it.internal_type IN (202,204)

GROUP

BY it.parent_id) AS a4 ON (a4.parent_id = a1.object_id)

INNER

JOIN sys.all_objects a2 ON ( a1.object_id = a2.object_id )

INNER

JOIN sys.schemas a3 ON (a2.schema_id = a3.schema_id)

inner

join sys.indexes SI ON (SI.object_id = a1."object_id")

inner

join sys.index_columns SIC ON (SIC.object_id = SI.object_id and SIC.index_id = SI.index_id)

left

outer join sys.dm_db_index_usage_stats US ON (US.object_id = SI.object_id and US.index_id = SI.index_id and US.database_id = db_id())

left

outer join sys.dm_db_index_operational_stats(NULL,NULL,NULL,NULL) IStats ON (IStats.object_id = SI.object_id and IStats.index_id = SI.index_id and IStats.database_id = db_id())

WHERE

a2.type <> N'S' and a2.type <> N'IT'

order

by row_count desc

-- Populate key string

declare

IndexCursor cursor for

select

F_Obj_ID, F_Index_ID from z_IUQ2_Temp_Index_Keys

for

update of Index_Key_List

declare

@objID int

declare

@IndID int

declare

@KeyString VARCHAR(MAX)

set

@KeyString = NULL

open

IndexCursor

set

nocount on

fetch

next from IndexCursor into @ObjID, @IndID

while

@@fetch_status = 0 begin

set

@KeyString = ''

select

@KeyString = COALESCE(@KeyString,'') + F_Column_Name + ', '

from

z_IUQ2_Temp_Index_Keys

where

F_Obj_ID = @ObjID and F_Index_ID = @IndID

ORDER

BY F_Index_ID, F_Index_Column_ID

set

@KeyString = LEFT(@KeyString,LEN(@KeyString) -2)

update

z_IUQ2_Temp_Index_Keys

set

Index_Key_List = @KeyString

where

current of IndexCursor

fetch

next from IndexCursor into @ObjID, @IndID

end

;

IndexCursor

deallocate

IndexCursor

-- clean up table to one line per index

delete

from z_IUQ2_Temp_Index_Keys

where

[F_Index_Column_ID] > 1

-- Select results

select

[F_Table_Name] TableName

[F_Row_Count] No_Of_Records

[F_Data] Data_Size

[F_Index_Size] Index_Size

[F_Index_Name] Index_Name

[F_User_Updates] Index_Updates

[F_User_Reads] Index_Reads

case

when

F_User_Reads = 0 then F_User_Updates

else

F_User_Updates / F_User_Reads

end

as Updates_Per_Read,

[F_Locks] Locks

[F_Blocks] Blocks

[F_Block_Wait_Time] Block_Wait_Time

[F_Last_Used] Index_Last_Used

[F_Index_Type] Index_Type

[Index_Key_List] Index_Fields

from

z_IUQ2_Temp_Index_Keys

--order by F_Row_Count desc, F_Table_Name, [F_Index_ID]

--order by F_User_Updates desc

--order by Blocks desc

--order by Block_Wait_Time desc

--order by Updates_Per_Read desc

order by F_Table_Name

Table Information including Index information (Usage, Blocks and Reads)

Additional resources