Transact-SQL Reference
SET STATISTICS IO
Causes Microsoft® SQL Server™ to display information regarding the amount of disk activity generated by Transact-SQL statements.
Syntax
SET STATISTICS IO { ON | OFF }
Remarks
When STATISTICS IO is ON, statistical information is displayed. When OFF, the information is not displayed.
After this option is set ON, all subsequent Transact-SQL statements return the statistical information until the option is set to OFF.
There are five output items.
| Output item | Meaning |
|---|---|
| Table | Name of the table. |
| scan count | Number of scans performed. |
| logical reads | Number of pages read from the data cache. |
| physical reads | Number of pages read from disk. |
| read-ahead reads | Number of pages placed into the cache for the query. |
The setting of SET STATISTICS IO is set at execute or run time and not at parse time.
Permissions
SET STATISTICS IO permissions default to all users.