AUTOLOCATE configuration parameter

Use the AUTOLOCATE configuration parameter to enable the automatic location of databases, indexes, and tables, and the automatic fragmentation of tables.

onconfig.std and default value
AUTOLOCATE 0
values
0 = Disable automatic location and fragmentation.

1 - 32 = Enable automatic location and fragmentation. The number indicates how many round-robin fragments to initially allocate to a table.

takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in memory and in your onconfig file by running the onmode -wf command.
When you reset the value dynamically in memory by running the onmode -wm command.

Usage

Use the AUTOLOCATE configuration parameter to control whether the database server controls the location of new databases, indexes, and tables and the fragmentation of those tables. If you set the AUTOLOCATE configuration parameter to a positive integer, the database server performs the following tasks:

  • Stores new databases for which you do not specify a location in the optimal dbspace instead of in the root dbspace. By default, all dbspaces except dbspaces that are dedicated to tenant databases are available. However, you can control the list of available dbspaces.
  • Fragments new tables by round-robin, where the number of fragments is equal to the value of the AUTOLOCATE configuration parameter.
  • Adds more table fragments as the table grows.

If you set the value of the AUTOLOCATE configuration parameter to 0, new databases are created in the root dbspace by default. New tables and indexes are created in the same dbspace as the database and are not fragmented.

Automatic location is not applicable to tenant databases or the tables, fragments, and indexes within tenant databases.

You can override the automatic location of a database by specifying a dbspace with the IN clause in the CREATE DATABASE statement. Similarly, you can override the automatic location and fragmentation of a table by specifying a dbspace with the IN clause or a fragmentation strategy with the FRAGMENT BY clause in the CREATE TABLE statement.

When this configuration parameter is enabled, you can use the autolocate database arguments with the admin() or task() function to:
  • Manage the list of dbspaces for automatic location and fragmentation. The list of available dbspaces is in the sysautolocate system catalog table.
  • Disable automatic location and fragmentation for the specified database.

You can use the AUTOLOCATE environment option of the SET ENVIRONMENT statement of SQL to enable or disable the value of the AUTOLOCATE configuration parameter for a session.


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