Removing tables from an accelerator

Follow the steps in this topic to remove accelerator-shadow tables from an accelerator.

About this task

If a part or all of a table (all partitions) have been archived by the High Performance Storage Saver, then this table (an accelerator-archive table) cannot be removed without first restoring the archived data. After restoring the data, the table remains on the accelerator, but becomes an ordinary accelerator-shadow table, which means that it can be removed.

If you remove a table from Db2 for z/OS®, you also have to remove the corresponding accelerator-shadow table from all of your accelerators. That is, you have remove each copy of the accelerator-shadow table in a separate, manual step, either by following the procedure below or by running the SYSPROC.ACCEL_REMOVE_TABLES stored procedure. The only exception are tables that are replicated by the IBM Integrated Synchronization function. In this case, the accelerator-shadow tables are removed automatically when you remove the original Db2 tables.

The table removal task is carried out by the SYSPROC.ACCEL_REMOVE_TABLES stored procedure on your data server. For information about the privileges that are required to run this procedure and further details, follow the appropriate Related reference link at the end of this topic.

Procedure

  1. Connect to the Db2 subsystem or data sharing group that the accelerator is attached to. For more information, see Connecting to a database server.
  2. Select the accelerator. For more information, see Selecting an accelerator.
  3. Select the tables that you want to remove.
    IBM Db2 Analytics Accelerator Studio Select the appropriate check boxes in front of the schema or table names. Selecting a schema name leads to the removal of all tables in that schema.
    IBM Data Server Manager Select the appropriate check boxes in front of the schema or table names. Selecting a schema name leads to the removal of all tables in that schema.
    IBM Unified Experience for z/OS
    1. Click the Tables tab.
    2. Select the appropriate check boxes in front of the schema or table names. Selecting a schema name leads to the removal of all tables in that schema.
    IBM Db2 Analytics Accelerator Administration Services N/A
  4. Remove the tables:
    IBM Db2 Analytics Accelerator Studio Click Remove on the toolbar.
    IBM Data Server Manager Click Remove on the toolbar.
    IBM Unified Experience for z/OS From the Take action drop-down button on top of the list of tables, select Remove.

    If some of the specified tables you want to remove have been archived by the High Performance Storage Saver, select Remove archive. This setting will also remove archived tables.
    IBM Db2 Analytics Accelerator Administration Services
    1. Start a /table/removeTablesFromAccelerator request.
    2. In the request body, specify the connection name and the accelerator name.
    3. Specify the tables to remove in an array that serves as the value of the "selTables" parameter. The first-level elements in this array must be JSON objects (key-value pairs), in which the key is the schema name, followed by the value, which is an array that contains the names of the tables belonging to that schema. Separate these table names by a comma. Also separate the JSON objects by a comma. Example:
      "selTables": [
    {
      "SYSABC": [
        "TABLE01",
        "TABLE02"
      ]
    },
    {
      "SYSDEF": [
        "TABLE01"
      ]
    }
  ],
    4. Set the "forceArchiveRemove": parameter to the value true if some of the tables to be removed have been archived by the High Performance Storage Saver. This setting will also remove archived tables.
    5. Click Execute.
    Attention: If federated access is enabled for a table that you want to remove, you are presented with an additional warning in a confirmation dialog when your administration client queries the SYSACCEL.SYSACCELERATEDTABLESAUTH table. The text in that dialog reads 
    Federated access has been granted to one or more of the tables you selected.
 Do you really want to remove these tables from the accelerator?

    However, if SYSACCEL.SYSACCELERATEDTABLESAUTH cannot be queried for some reason, this dialog does not come up, and the selected tables are removed as if there were no tables with federated access.

  5. Confirm the removal by clicking Yes in the Remove Table window.
    IBM Db2 Analytics Accelerator Studio Click Yes in the Remove Table window.
    IBM Data Server Manager Click Yes in the Remove Table window.
    IBM Unified Experience for z/OS Click Remove in the Remove table window.
    IBM Db2 Analytics Accelerator Administration Services N/A