Background documentationDatabase Parameters Locate this document in the navigation structure


Database parameters define fundamental properties of the database.

When creating a new database, you can use the system default for the database parameter values, copy the database parameter file from a different database, or else import the database parameter file from a complete data backup.

Database parameters are divided into the following groups:

Note Note

Starting with version 7.7.03 of the database software, the names of many database parameters have changed.

Some database parameters have also been designated obsolete. These parameters have either been removed already or will be removed in one of the next database versions.

More information: Obsolete Database Parameters

End of the note.
Database Parameter File

The database system saves the values of the database parameters in binary format in the PARAM database parameter file of the database.

Caution Caution

Do not change database parameter values directly in this file, but as described below.

End of the caution.

The default parameter file cserv.pcf contains the default values, value ranges, calculation formulas and properties of the database parameters.

More information:

Changing Database Parameters

You can change the values of most database parameters.

Most changes to database parameters take effect only after the database has been restarted.

However, you can change individual database parameters while the database is running, that is in the ONLINE or ADMIN operational state (see the description of individual database parameters for more information). For these changes you can define when they are to become effective:

  • Until the next restart

  • After the next restart

  • Immediately and permanently

If you change a database parameter whose value is normally calculated by the system, then the system will consider this user-defined value for all subsequent recalculations of database parameter values. The system discards and recalculates this user-defined value only if it is not within the permitted value range (for example, after the database software has been updated).

Use one of the following database tools:

Database Studio, Database Manager CLI, or CCMS (in SAP systems only)

More information:

You can also use these tools to display the history of the values of the database parameters.

More Information

SAP Note 1139904 (FAQ MaxDB/liveCache Kernel Parameter)