OPEN PERM GROUP command

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Summary

Privileges
Any user
Function
Opens a permanent Model 204 group

Syntax

OPEN [PERM] [GROUP] groupname

Where: groupname is the name of the Model 204 file group to be opened.

Example

OPEN PERM GROUP WEEK *** M204.0619: GROUP FILE OPENED: WEEK

Usage notes

A Model 204 file is a collection of records. A file group is a collection of Model 204 files that Model 204 treats logically as a single file. An individual file can be a member of several different groups. Any user can open several files or groups during a single Model 204 session. These remain open until a CLOSE, LOGOUT, or DISCONNECT command is issued or until the user is restarted.

There are three types of permanent groups:

  • Public

  • semi-public

  • Private

Opening a permanent group is very similar to opening a file. If the group is public, Model 204 opens it without asking for a group password. You are given the default group privileges assigned to the group by the system manager.

If the group is semi-public or private, Model 204 asks you to enter a valid password by prompting, as shown below:

*** M204.0347: PASSWORD password [:new password]

where password or new password is a valid password for the group to be opened (one to eight characters). It cannot contain spaces, commas, or colons.

Each group can have several passwords defined for it. If you enter a valid password, the group is opened with the group privileges that are associated with that password. If you do not know the password for the group and simply enter a carriage return, the group is opened and you are given the default privileges for the group. An invalid password also causes the group to be opened with its default privileges.

For a private group, you must enter a valid password or the group is not opened.

Passwords used to open a permanent group can be changed in exactly the manner described for file passwords.

Once Model 204 has determined group privileges for a public, semi-public, or private group, it opens all of the files in the group. Unlike the temporary group OPEN, the permanent group OPEN does not notify you that the individual member files are being opened. In addition, you are not prompted for individual file passwords. After all member files have been opened, Model 204 displays a message informing you that the group is open. If the group privileges include the ability to update, the following message is displayed:

*** M204.0619: GROUP FILE OPENED: groupname

If the group privileges do not allow update, or if Model 204 is running RESTART to perform recovery, the following is displayed:

*** M204.0619: GROUP groupname OPENED -- NO UPDATES ALLOWED

If any of the files in the permanent group cannot be opened, Model 204 aborts the group OPEN and displays the following message:

*** M204.0864: GROUP OPEN FAILED, CLOSING PARTIAL GROUP

If a mandatory member of a Parallel Query Option/204 scattered group fails to open, the OPEN fails for the entire group. For more information about opening scattered groups, see PQO: Remote files and scattered groups.

Group privileges determine which operations you can perform on the group and its procedures.

With application subsystems, a user who opens a group defined as optional to the subsystem is granted the privileges assigned in the subsystem definition. A required member of the subsystem is opened implicitly when a user enters the subsystem.

OPEN processing of a permanent group

See The logic of OPEN command processing for a description of how Model 204 entities with the same name are handled.