STOP command: Making a file or group unavailable

Summary

Privileges

System administrator

Function

Makes a file or permanent group unavailable for use

Syntax

STOP {FILE | [PERM] GROUP} name [AT location]

Where:

name	is the name of a file or a group.
location	For Parallel Query Option/204 files, is the symbolic name (as many as eight characters) that refers to the location of the node on which the remote file resides. An unquoted equal sign (=) specifies that the file is local. If remote, must match a symbolic destination name specified in the DESTINATION parameter of the relevant local client DEFINE PROCESS command.

Usage notes

The STOP command allows the system administrator to specify that a file or permanent group is unavailable to users. It prevents the opening of both subsystem and non-subsystem files or groups.

The STOP command causes subsequent opens of the file or group to fail. This command has no effect on a user who has the file or group open when the STOP is issued until the user closes the file or group and then attempts to reopen it. If you attempt to reopen a stopped file or group without first closing it, the reopen succeeds.

The STOP command checks whether there is an active subsystem containing the named file or group as a required member. A file is checked for membership in all required groups. If the file or group is required by a subsystem, the STOP command is rejected with an error message. If the file or group is not required, it is marked unavailable for future use.

Model 204 scans the list of active subsystems looking for optional uses of the file or group. All affected optional members are marked as no longer available for future use, although they may be currently in use by a subsystem user. When all subsystem users indicate that they are finished with an affected member (by closing the member), Model 204 discards all precompiled code referring to the member, and reclaims the pages in the temporary file. Further attempts by subsystem users to open the stopped member fails until a START command is executed. During this period, another copy of Model 204 can process the file or group.

In PQO, the affect of STOP FILE depends on whether it is issued on a server node or on a client node. For information about STOP FILE and STOP GROUP when remote files are affected, see the Parallel Query Option/204 User's Guide.