Global Temporary Table

max_active_global_temporary_table

Parameter description: Specifies whether global temporary tables can be created. Currently, the Ustore engine does not support global temporary tables. The value of this parameter determines the memory reserved in the shared cache for hash tables required by global temporary tables. The total number of active global temporary tables in all sessions is not forcibly limited.

This parameter is a POSTMASTER parameter. Set it based on instructions provided in Table 1.

Value range: an integer ranging from 0 to 1000000

• 0: The global temporary table function is disabled.
• > 0: The global temporary table function is enabled.

Default value: 1000

vacuum_gtt_defer_check_age

Parameter description: Checks the differences between the global temporary table relfrozenxid and the ordinary table after VACUUM is executed. WARNING is generated if the difference value exceeds the specified parameter value. Use the default value for this parameter.

This parameter is a USERSET parameter. Set it based on instructions provided in Table 1.

Value range: an integer ranging from 0 to 1000000

Default value: 10000

enable_gtt_concurrent_truncate

Parameter description: Specifies whether to support concurrent execution of TRUNCATE TABLE and DML operations on global temporary tables and concurrent execution of TRUNCATE TABLE on global temporary tables.

This parameter is a SIGHUP parameter. Set it based on instructions provided in Table 1.

Value range: Boolean

• on/true indicates that the preceding operations can be performed concurrently.
• off/false indicates that the preceding operations cannot be performed concurrently.

Default value: on