auto_extend

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, use the function for the automatic extension of the data area.

The number of data volumes, which 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, Database Manager creates the new data volume in the run directory of the database.

You can activate and deactivate this function. As per the system default, 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 using the DBM command auto_extend and entering a new percentage. 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 permission ParamFull or AccessUtility.
The last data volume added is of the FILE type.

Structure

auto_extend <mode> [<percentage>]

Options
Option	Description
`<mode>`	Function for the automatic extension of the data area Possible values are: `ON`: Activate function `OFF`: Deactivate 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 the automatic extension of the data area is active
`<percentage>`	Defined percentage as of which the system adds a data volume
`OFF`	The function for the automatic extension of the data area is inactive
`<reason>`	Reason why the function was deactivated
`UNKNOWN`	The status of the function for the automatic extension of the data area cannot be determined

Example

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

>dbmcli -d DEMODB -u OLEG,MONDAY

dbmcli on DEMODB>

Switch on the function for the automatic extension of the data area. 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 the automatic extension of the data area:

dbmcli on DEMODB>auto_extend SHOW

OK

ON 66

More Information

Concepts of the Database System, Volumes (Permanent Storage)