Wednesday, October 1, 2008

Getting a SQL Server RowCount Without doing a Table Scan

Sometimes there is a need to get record counts from every table in your database. One way of doing this is to do a SELECT count(*) on all of your tables, but this could create a lot of overhead especially for large databases and large tables. If you don't require an exact answer, it isn't necessary to use a SELECT count(*) query on the rows in a table to get the row count.

SQL Server keeps the row count in sysindexes and it can be retrieved there. The key is to select the correct record from sysindexes. Sysindexes is a system table that exists in every database.

SQL Server maintains at least one row in sysindexes for every user table. A few of the most important columns are:

Column Data Type Description
id int ID of the table referred to by this row
indid int See the text that follows...
rowcnt bigint Number of rows in the index

The indid column tells us what part of the table structure this row of sysindexes is referring to:

indid value Description
0 Table data when there is no clustered index
1 Refers to the clustered index
2 - 254 Non-clustered indexes
255 Text or Image data pages

A table will only have an entry in sysindexes with an indid value of for 0 or 1, never both. That's the entry that we're interested in because its rowcnt field gives us the number of rows in the table. Here is a query that shows the table, index and indid from the pubs database:

USE pubs

SELECT so.[name] as [table name]
, CASE WHEN si.indid between 1 and 254
AS [Index Name]
, si.indid
FROM sysindexes si
INNER JOIN sysobjects so
ON =
WHERE si.indid < 2
AND so.type = 'U' -- Only User Tables
AND so.[name] != 'dtproperties'
ORDER BY so.[name]

Here are the results:

table name Index Name indid
authors UPKCL_auidind 1
discounts NULL 0
employee employee_ind 1
jobs PK__jobs__117F9D94 1
pub_info UPKCL_pubinfo 1
publishers UPKCL_pubind 1
roysched NULL 0
sales UPKCL_sales 1
stores UPK_storeid 1
titleauthor UPKCL_taind 1
titles UPKCL_titleidind 1

As you can see from the results, most of the indexes are clustered (indid=1) but a few tables such as discounts don't have a clustered index (indid=0).

I started this tip with "If you don't need an exact answer..." That's because there are times when rowcnt is not the exact number of records in the table.

This can be corrected by updating statistics on the table with:

dbcc updateusage

Here's the CREATE FUNCTION script for udf_Tbl_RowCOUNT


@sTableName sysname -- Table to retrieve Row Count

RETURNS INT -- Row count of the table, NULL if not found.

* Returns the row count for a table by examining sysindexes.
* This function must be run in the same database as the table.
* Common Usage:
SELECT dbo.udf_Tbl_RowCOUNT ('')

* Test
PRINT 'Test 1 Bad table ' + CASE WHEN SELECT
dbo.udf_Tbl_RowCOUNT ('foobar') is NULL
THEN 'Worked' ELSE 'Error' END

* © Copyright 2002 Andrew Novick
* You may use this function in any of your SQL Server databases
* including databases that you sell, so long as they contain
* other unrelated database objects. You may not publish this
* UDF either in print or electronically.


DECLARE @nRowCount INT -- the rows
DECLARE @nObjectID int -- Object ID

SET @nObjectID = OBJECT_ID(@sTableName)

-- Object might not be found
IF @nObjectID is null RETURN NULL

SELECT TOP 1 @nRowCount = rows
FROM sysindexes
WHERE id = @nObjectID AND indid < 2

RETURN @nRowCount


Let's use it:

use pubs -- assuming the UDF was created in pubs

SELECT [name]
, dbo.udf_Tbl_RowCOUNT ([name]) as [Row Count]
FROM sysobjects
WHERE type='U' and name != 'dtproperties'
ORDER BY [name]

Here are the results:

name Row Count
authors 24
discounts 3
employee 43
jobs 14
pub_info 8
publishers 8
roysched 86
sales 21
stores 6
titleauthor 25
titles 18

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