SUBORDERS

This statement makes SQL scans and logical files available.

Definition

A lower-level DBH option of SYSTEM-LIMITS

Function

You use the DBH option SUBORDERS to specify the number of suborders for which resources are to be provided during the DBH session. This restricts main-memory requirements.

The meaning of suborders differs depending on whether it applies to an SQL or a CALL DML application:

• In the case of an SQL application, suborders are SQL scans, i.e. subareas of an SQL access plan, the evaluation rule for an SQL statement.

• In the case of a CALL DML application, suborders are logical files for CALL DML requests.

SUBORDERS

= *STD / *PARAMETERS(...)
	*PARAMETERS(...)
		|	INITIAL = 24 / <integer 6..262143>
		|	,MAXIMUM = *STD / <integer 6..262143>

Operands

SUBORDERS = *STD

The default numbers of SQL scans or logical files (suborders) permitted apply. These are described under *PARAMETERS.

SUBORDERS = *PARAMETERS(...)

INITIAL = 24 / <integer 6..262143>

Initial value for the number of concurrent suborders for which resources are to be available.

The default value for INITIAL is 24.

An internal comparison ensures that the permissible number of suborders is at least as high as the maximum number of concurrent users (see the DBH option USERS on "USERS"). If the maximum number of concurrent users is greater than the value specified here, the initial value is increased automatically.

MAXIMUM = *STD / <integer 6..262143>
Maximum permissible number of concurrent suborders.
If the initial value specified for the INITIAL operand is not high enough, SESAM/SQL allows resources to be made available dynamically for additional suborders. The default value for MAXIMUM is the initial value for the permissible number of concurrent suborders specified by means of the INITIAL operand.

You can change the maximum value for the permissible number of concurrent suborders during the DBH session by means of the MODIFY-SUBORDER-LIMIT administration statement(see "MODIFY-SUBORDER-LIMIT").

Information on suborders

You will find the number of used suborders and the maximum number of available suborders in the “SYSTEM INFORMATION” form of the SESAM/SQL monitor SESMON (see "DBH form SYSTEM INFORMATION").

The “ Performance” manual describes the cases in which it makes sense to modify the number of available resources for suborders at the next DBH startup.