SQL/MX 3.1 Installation and Management Guide (H06.23+, J06.12+)

Reviewing and Setting System Defaults
HP NonStop SQL/MX Release 3.1 Installation and Management Guide—663852-001
6-2
Consequences of Inserting Rows Into the
SYSTEM_DEFAULTS Table
The statements in this example update the current default setting for the transaction
isolation level on \MYSYS:
SET SCHEMA nonstop_sqlmx_mysys.system_defaults_schema;
UPDATE SYSTEM_DEFAULTS
SET ATTR_VALUE = 'READ COMMITTED'
WHERE ATTRIBUTE = 'ISOLATION_LEVEL';
The system-defined default settings can be viewed in MXCI using the showcontrol
all command or by using following query:
select * from table(compilercontrols()) where type = 'CQD' and
state = 'DEF_TAB';
The COMPILERCONTROLS is the table-valued stored procedure, which is implemented
from the compiler. For information on the COMPILERCONTROLS function, see the
SQL/MX Reference Manual.
Consequences of Inserting Rows Into the
SYSTEM_DEFAULTS Table
Changes you make through the SYSTEM_DEFAULTS table are permanent until
changed by a DELETE statement or another UPDATE statement. However, the values
you insert into the SYSTEM_DEFAULTS table do not affect your current session
immediately. You must exit and then reenter the MXCI session for these values to take
effect as system-level default settings. In addition, these insertions do not affect
previously compiled modules until you recompile them.
If an attribute has a value in the SYSTEM_DEFAULTS table and a CONTROL QUERY
DEFAULT statement, a CONTROL TABLE statement, or a SET TABLE statement is
issued for that attribute, the value specified by CONTROL QUERY DEFAULT takes
precedence over the value in the SYSTEM_DEFAULTS table for the current session.
For more information about the system defaults for NonStop SQL/MX and the
SYSTEM_DEFAULTS metadata table, see the SQL/MX Reference Manual.
System Default Settings to Review After
Installing SQL/MX Release 3.x
Alternative Settings For Selected System Defaults
Table 6-1 lists the system defaults that you must change after you install SQL/MX
Release 3.1 and before you run your applications. For more information about all the
system defaults, see the SQL/MX Release 3.1 Reference Manual.