BATCH

Function

The BATCH command enables you to specify how batch jobs will be processed.

Description

To run jobs in batch mode, the application must be started up in batch mode.

When you enter the application interactively, you are allowed three attempts at giving your correct username and password. When the application is started up in batch mode, only one attempt is permitted. If either the username or password are incorrect, control will pass back to the operating system and that job will be terminated.

Copying Databases for Batch Processing

The BATCH COPY command allows you to take copies of DBs with Read/Write access, provided you have Read/Write access to the database. The batch job accesses these copies and so allows interactive users to carry on using the normal copies. Write access to copies of DBs is needed to allow functions such as automatic group creation to be carried out.

By default, if a COPY command is not given, copies are made of all Design DBs.

If copies are not taken of DBs, then the originals are accessed in Read-only mode, irrespective of the normal access rights (which may be Read/Write).

You can specify that you want all the databases of a given type to be copied, for example, all the PADD databases, or you can specify named databases, all databases or none. You can specify a group of databases of a given type, and then use the NOCOPY option to stop copies of named databases or specified types of database being made.

The copies taken by the BATCH COPY command are temporary. They disappear when the batch job exits from the application (whether successfully completed or not) or when the batch file selects a new MDB. If permanent copies are required, they must be made by the System Administrator using Admin.

Access to databases through Admin and RECONFIGURER can only be made in Read-only mode, even if the databases have been copied with Read/Write access. Any attempt to alter the project structure for batch jobs, even temporarily, will result in the message:

Trying to alter a read-only database

Example

COPY commands are additive; that is, each new COPY command is added to the result of all previous COPY commands. For example, consider an MDB containing the following DBs:

MASTER/CATA                 CATA
PIPING/DES74A               DESI
PIPING/DES75A               DESI
PIPING/DES37C               DESI
CIVIL/DES74A                DESI
CIVIL/DES75A                DESI
CIVIL/DES37C                DESI
MATS/PROP2                  PROP

If the batch file contains the commands:

BATCH  COPY  NONE
BATCH  COPY  PIPING/DES75A  PIPING/DES37C
BATCH  COPY  DRWG

The following DBs would be marked as requiring copies:

PIPING/DES75A              DESI
PIPING/DES37C              DESI

How Monitor Accesses Databases in Batch Mode

For a batch job to start, the application must be able to access all the databases it needs, either to make copies of them or to access them directly.

When a batch run starts, and the first module change command occurs, Monitor will make copies of any DBs marked for copying.

As the batch file could alter the status of databases in an MDB by using the DEFER, CURRENT or EXCHANGE commands, or could change to a different MDB, copies are not taken until immediately after the command to change to another module. If a new MDB is selected, or the same MDB is reselected and copies of DBs exist from the last time the MDB was accessed, then all existing copies are deleted and fresh copies are taken. It is important for batch users to assess the effect of copying DBs on disk space.

Error Handling in Batch Mode

• If the project name, username or password are incorrectly specified while trying to gain access in batch mode, the application will immediately abort.

• If any other errors occur, the batch job will immediately be aborted, unless PML error handling has been used. Refer to Variables, Objects, Functions and Methods for information about PML.

Security

When you use the batch facilities, you must put your username and password into a file. This is a potential breach of the security system provided by the application, from two points of view.

• Unless the batch file is protected from access by other users, they will be able to read it and find out the username and password contained in it. You should make sure that operating system security is used to protect batch files.

• Many batch systems operate by taking a copy of the file submitted for batch execution. If this copy is held somewhere accessible to normal (non-system) users, then even if the user submitting the job has protected his own files, his username and password could still be read from the copy. Project Coordinators should consult their Computer Systems department to make sure that this is not the case on their particular computer.

Data Integrity in Batch Mode

There is some risk of corruption of the COMMS DB (the only DB written to in Read-only batch operation) if a batch-mode job is interrupted before completion.

To reduce the risk of serious corruption of the COMMS DB, you should take the following precautions:

• Do not send remote instructions to abort a batch job. The job interruption could occur while the COMMS DB is being updated.

• Do not use batch queues where CPU or elapsed time restrictions are in force.

• Do not execute batch jobs if there is a risk of running out of disk space.

Command Syntax

                            .----------<---------.
                           /                     |
>-- BAtch ---+--- COpy ---*--- ALL --------------|
             |            |                      |
             |            |--- NONE -------------|
             |            |                      |
             |            |--- dbtype -----------|
             |            |                      |
             |            ‘--- dbname -----------|
             |                                   |
             |                .-----<------.     |
             |               /             |     |
             ‘--- NOCOpy ---*--- dbtype ---|     |
                            |              |     |
                            ‘--- dbname ---+-----+--->

where dbtype is one of the following:

DESI CATA PROP PADD DICT ISOD