onmode and S arguments: Set maximum number of decision-support scans (SQL administration API)

Use the onmode and S arguments with the admin() or task() function to change the maximum number of concurrently executing decision-support scans for the current session.

Syntax

Read syntax diagramSkip visual syntax diagram
>>-EXECUTE FUNCTION--+-admin-+--(------------------------------->
                     '-task--'      

>--"onmode"--,--"S"--,--"scans"--)--;--------------------------><

Element Description Key Considerations
scans The maximum number of concurrently executing parallel scans. The number must be an unsigned integer from 10 to 1 048 576.

Usage

Use this function to override the limit set by the DS_MAX_SCANS configuration parameter while the database server is online. The new value affects only the current instance of the database server; the values are not recorded in the ONCONFIG file. If you shut down and restart the database server, the value of the parameter reverts to the value in the ONCONFIG file.

For information on parameters used for controlling PDQ, see the HCL Informix® Performance Guide.

This function is equivalent to the onmode -S command.

Example

The following example sets the maximum number of concurrently executing parallel scans to 2000:
EXECUTE FUNCTION task("onmode","S","2000");

Copyright© 2019 HCL Technologies Limited