Feb 4, 2011

List of SQL Server tables and their row counts

The most straightforward method for determining the number of rows in a table, is to use the following:

SELECT COUNT(*) FROM tablename

You can also use the system stored procedure, sp_spaceused, to determine other information, such as data and index size:

EXEC sp_spaceused 'tablename'

To get an *approximate* count for all tables, you can use the following:

SELECT
    [TableName] = so.name,
    [RowCount] = MAX(si.rows)
FROM
    sysobjects so,
    sysindexes si
WHERE
    so.xtype = 'U'
    AND
    si.id = OBJECT_ID(so.name)
GROUP BY
    so.name
ORDER BY
    2 DESC

The sysindexes table is usually a little bit inaccurate, because it is not updated constantly. It will also include the 'dtproperties' table, which is one of those hybrid tables that falls neither under the 'system' nor 'user' category. It does not appear in Enterprise Manager's "Tables" view if you choose to hide system objects, but it shows up above.

In any case, it is generally not recommended to query against the system objects directly, so please only use the above for rough, ad-hoc guesstimates.

Undocumented methods

Please don't rely on these methods, or use them in production code. Undocumented stored procedures may change or be disabled in a future release, or even a service pack / hotfix; or, they could disappear altogether.

The following creates your own diagnostic page to give you a quick overview of how many rows are in each table in a specific database. It uses my favorite of the undocumented, do-not-use-in-production system stored procedures, sp_MSForEachTable:

CREATE PROCEDURE dbo.listTableRowCounts
AS
BEGIN
    SET NOCOUNT ON

    DECLARE @SQL VARCHAR(255)
    SET @SQL = 'DBCC UPDATEUSAGE (' + DB_NAME() + ')'
    EXEC(@SQL)

    CREATE TABLE #foo
    (
        tablename VARCHAR(255),
        rc INT
    )
   
    INSERT #foo
        EXEC sp_msForEachTable
            'SELECT PARSENAME(''?'', 1),
            COUNT(*) FROM ?'

    SELECT tablename, rc
        FROM #foo
        ORDER BY rc DESC

    DROP TABLE #foo
END

(The only reason a #temp table is used here is because we want the results ordered by largest row counts first. If the order can be arbitrary, you can just run the EXEC by itself.)

If you want to run it from ASP, you can call it as follows:

<%
    set conn = CreateObject("ADODB.Connection")
    conn.open "<connection_string>"
    set rs = conn.execute("EXEC dbo.listTableRowCounts")
    if not rs.eof then

        response.write "<table><tr>" & _
            "<th>Table name</th>" & _
            "<th>Rows</th></tr>"

        do while not rs.eof
            response.write "<tr>" & _
                " <td>" & rs(0) & "</td>" & _
                " <td>" & rs(1) & "</td>" & _
                "</tr>"
            rs.movenext
        loop

        response.write "</table>"
    end if
    rs.close: set rs = nothing
    conn.close: set conn = nothing
%>

Note that this will only count USER tables, not system tables. You could consider creating this procedure in the master database and marking it as a system object; this way, you could execute it within the context of any database, instead of having to create a copy of the proc for each database.

Replicating 'Taskpad / Table Info' view

Several people have asked how to mimic what taskpad view in Enterprise Manager does for Table Info, without having to scroll or search to find tables, and without listing all of the (largely superfluous and mostly built-in) index names. This view shows all the tables, rowcounts, reserved size and index size. Here is a stored procedure that does it one better... it essentially fires an sp_spaceused (which includes data and free space, in addition to reserved and index size). Now, before you use it, please exercise caution. This relies on system tables, and the undocumented sp_msForEachTable. Its behavior may change between versions and service packs, so don't rely on it for production code.

CREATE PROCEDURE dbo.allTables_SpaceUsed
AS
BEGIN
    SET NOCOUNT ON    

    DBCC UPDATEUSAGE(0)

    CREATE TABLE #t
    (
        id INT,
        TableName VARCHAR(32),
        NRows INT,
        Reserved FLOAT,
        TableSize FLOAT,
        IndexSize FLOAT,
        FreeSpace FLOAT
    )

    INSERT #t EXEC sp_msForEachTable 'SELECT
        OBJECT_ID(PARSENAME(''?'',1)),
        PARSENAME(''?'',1),
        COUNT(*),0,0,0,0 FROM ?'

    DECLARE @low INT

    SELECT @low = [low] FROM master.dbo.spt_values
        WHERE number = 1
        AND type = 'E'

    UPDATE #t SET Reserved = x.r, IndexSize = x.i FROM
        (SELECT id, r = SUM(si.reserved), i = SUM(si.used)
        FROM sysindexes si
        WHERE si.indid IN (0, 1, 255)
        GROUP BY id) x
        WHERE x.id = #t.id

    UPDATE #t SET TableSize = (SELECT SUM(si.dpages)
        FROM sysindexes si
        WHERE si.indid < 2
        AND si.id = #t.id)

    UPDATE #t SET TableSize = TableSize +
        (SELECT COALESCE(SUM(used), 0)
        FROM sysindexes si
        WHERE si.indid = 255
        AND si.id = #t.id)

    UPDATE #t SET FreeSpace = Reserved - IndexSize

    UPDATE #t SET IndexSize = IndexSize - TableSize

    SELECT
        tablename,
        nrows,
        Reserved = LTRIM(STR(
            reserved * @low / 1024.,15,0) +
            ' ' + 'KB'),
        DataSize = LTRIM(STR(
            tablesize * @low / 1024.,15,0) +
            ' ' + 'KB'),
        IndexSize = LTRIM(STR(
            indexSize * @low / 1024.,15,0) +
            ' ' + 'KB'),
        FreeSpace = LTRIM(STR(
            freeSpace * @low / 1024.,15,0) +
            ' ' + 'KB')
        FROM #t
        ORDER BY 1

    DROP TABLE #t
END

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