SQL/MX 3.1 Reference Manual (H06.23+, J06.12+)

Metadata Tables
HP NonStop SQL/MX Release 3.1 Reference Manual—663850-001
10-83
Examples of SYSTEM_DEFAULTS Table
•
Query the SYSTEM_DEFAULTS table to obtain the current default setting for the
transaction isolation level:
SELECT ATTRIBUTE, ATTR_VALUE FROM SYSTEM_DEFAULTS
WHERE ATTRIBUTE = 'ISOLATION_LEVEL';
•
Set a new value for the transaction isolation level:
UPDATE SYSTEM_DEFAULTS
SET ATTR_VALUE = 'READ COMMITTED'
WHERE ATTRIBUTE = 'ISOLATION_LEVEL';
•
Set the level of optimization for the next query to be executed. The CONTROL
QUERY DEFAULT statement does not change the settings of the
SYSTEM_DEFAULTS table.
CONTROL QUERY DEFAULT OPTIMIZATION_LEVEL '0';