Purpose
Sets the DBQL cache size and determines whether DBQL uses 64K or 1MB data blocks.
The size of the DBQLParamTbl cache, populated when you begin query logging with the PARAMINFO option, is controlled separately by the DBQLLOBCacheSize DBS Control field.
Field Group
Performance
Valid Range
0 through 16 MB
A value of zero sets the DBQL cache size to 64 K, and causes DBQL to use 64 K data blocks. Any other value causes DBQL to use 1 MB data blocks.
Default
2
Changes Take Effect
After the next Teradata Database restart.
Usage Notes
- Increasing the DBQL cache size can reduce the overhead associated with frequent cache flushing. This can be beneficial on extremely busy systems that experience resource contention or exhaustion.
- Changing DBQLDefCacheSize invalidates the contents of the DBQL caches at the next Teradata Database restart. Teradata recommends that you flush all DBQL caches prior to restarting the database. Use the following SQL statement:
FLUSH QUERY LOGGING WITH ALL;
Related Topics
| For more information on… | See… |
|---|---|
| BEGIN QUERY LOGGING, END QUERY LOGGING, and FLUSH QUERY LOGGING statements | Teradata Vantage™ - SQL Data Definition Language Syntax and Examples, B035-1144. |
| tracking processing behavior with the DBQL | Teradata Vantage™ - Database Administration, B035-1093. |
| DBQLLOBCacheSize field | DBQLLOBCacheSize |