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You can configure your database system in such a way that it automatically adds a new data volume as soon as the fill level of the data area reaches a certain percentage. To do this, you use the automatic extension of data area function.

The number of data volumes that can be added while the database is in operation is limited by the value of the MaxDataVolumes database parameter. The name of the new data volume is determined by the system based on the existing volume definitions.

You can use the Database Manager parameter AutoExtDir to define the directory in which the new data volume is to be created (see: dbm_configset). If this parameter is not defined, the Database Manager creates the new data volume in the run directory of the database instance.

You can activate and deactivate this function. The system default for this function is on and the system adds a new data volume to the data area as soon as the fill level reaches 90%.

You can change the fill level threshold by executing the DBM command auto_extend and entering a new value. This remains valid until you change it again.

If you activate this function and do not enter a percent value, the percent value defined last time is used.

Note Note

Like other DBM commands, this one requires its own event task. For this reason, make sure when you switch on this function that the FloatingServiceTasks and PreservedEventTasks database parameter values are large enough.

Also make sure that the X server is running since the auto_extend function only works if X server is running on the database computer.

End of the note.

Prerequisites

  • You have the server authorization ParamFull or AccessUtility.

  • The last data volume that you added is of the file type.

Structure

auto_extend <mode> [<percentage>]

Options

Option

Description

<mode>

Function for automatically extending the data area. Possible values are:

ON: Enable function

OFF: Disable function

SHOW: Display function

<percentage>

Percentage at which the system is to add a new data volume

The following applies: 1 ≤ <percentage> ≤ 100

The default value is 90

Result

OK

[ON [<percentage>] | OFF [, <reason> | UNKNOWN]

Values for the Reply Fields

Value

Description

ON

The function for automatically extending the data area is active

<percentage>

Defined percentage as of which the system adds a data volume

OFF

The function for automatically extending the data area is not active

<reason>

Reason why the function was deactivated

UNKNOWN

The status of the function for automatically extending the data area cannot be determined

Example

Call the Database Manager CLI in session mode, log on as operator OLEG with the password MONDAY, connect to the database instance DEMODB:

>dbmcli -d DEMODB -u OLEG,MONDAY

dbmcli on DEMODB>

Switch on automatic extension of data area function. The system should add a data volume as soon as the data area is 66 % full:

dbmcli on DEMODB>auto_extend ON 66

OK

Display the status of the function for automatic extension of the data area:

dbmcli on DEMODB>auto_extend SHOW

OK

ON 66

More Information

Database Manager CLI Tutorial, Enlarging a Database Instance

Concepts of the Database System, Volumes (Permanent Storage)