OpenTP1 Version 7 Operation

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4.7.4 TAM table addition and removal

The tamadd command adds a TAM table to an online system. The loading time and access mode of the added TAM table depend on the options specified in the tamadd command. Once a TAM table has been added, it can be accessed in the online mode by releasing the TAM table from shutdown status with the tamrles command.

When the -i option of the tamadd command is specified, a TAM table serves as an I/O failure continuation table. If an I/O error occurs during updating of a TAM file, this file will not be placed in the error shutdown status. This means that the file can be accessed by any UAP operating in the same online mode. In order to prevent inconsistent TAM file status at restart of online operation, the TAM table with an error having occurred in the previous online operation (an I/O failure continuation table) will be removed from the online system. Once online operation has restarted, the TAM file must be recovered and added to the online system again.

When updating only a part of a long record, the journal amount can be reduced by collecting the journal of only the updated part. This is specified by the -j option in the tamadd command when adding a TAM table.

To remove a TAM table from the online system, the tamrm command is used.

A TAM table once removed from the online system can be added under the same TAM table name if the file attributes (record length, key length, etc.) are the same.