If you have ever performed a SELECT COUNT(*) on a very large table, you know how long it can take. For example, when I ran the following command on a large table I manage:
SELECT COUNT(*) from
It took 1:09 to count 10,725,948 rows in the table. At the same time, SQL Server had to perform a lot of logical and physical I/O in order to perform the count, chewing up important SQL Server resources.
A much faster, and more efficient, way of counting rows in a table is to run the following query:
SELECT rows
FROM sysindexes
WHERE id = OBJECT_ID('
When I run the query against the same table, it takes less than a second to run, and it gave me the same results. Not a bad improvement and it took virtually no I/O. This is because the row count of your tables is stored in the sysindexes system table of your database. So instead of counting rows when you need to, just look up the row count in the sysindexes table.
There is one potential downside to using the sysindexes table. And that this system table is not updated in real time, so it might underestimate the number of rows you actually have. Assuming you have the database option turned on to "Auto Create Statistics" and "Auto Update Statistics," the value you get should be very close to being correct, if not correct. If you can live with a very close estimate, then this is the best way to count rows in your tables.
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