UPDATE DATABASE CONFIGURATION command
The UPDATE DATABASE CONFIGURATION command modifies individual entries in a specific database configuration file. A database configuration file resides on every database partition on which the database has been created.
Scope
- MEMBER to update only one database member for a Db2® pureScale® environment, or to update only one database partition in a partitioned database environment.
Authorization
- SYSADM
- SYSCTRL
- SYSMAINT
Required connection
Instance. An explicit attachment is not required, but a database connection is recommended when the database is active. If the database is listed as remote, an instance attachment to the remote node is established for the duration of the command. To change a parameter online, you must be connected to the database.
Command syntax
Command parameters
- FOR database-alias
- Specifies the alias of the database whose configuration is to be updated. Specifying the
database alias is not required when a database connection has already been established. You can update
the configuration file for another database residing under the same database instance. For example,
if you are connected only to database
db11
, and issueupdate db config for alias db22 using .... immediate
:- If there is no active connection on
db22
, the update will be successful because only the configuration file needs to be updated. A new connection (which will activate the database) will see the new change in memory. - If there are active connections on
db22
from other applications, the update will work on disk but not in memory. You will receive a warning saying that the database needs to be restarted.
- If there is no active connection on
- MEMBER member-number
- The MEMBER clause specifies to which member the change should be applied. Omission of this clause results in the change being applied to all the members.
- USING config-keyword value
- config-keyword specifies the database configuration parameter to be updated. value specifies the value to be assigned to the parameter.
- AUTOMATIC
- Some configuration parameters can be set to AUTOMATIC, allowing Db2 database systems to automatically adjust these parameters to reflect the current resource requirements. For a list of configuration parameters that support the AUTOMATIC keyword, refer to the configuration parameters summary. If a value is specified along with the AUTOMATIC keyword, it might influence the automatic calculations. For specific details about this behavior, refer to the documentation for the configuration parameter.
- MANUAL
- Disables automatic tuning for the configuration parameter. The parameter is set to its current internal value and is no longer updated automatically.
- IMMEDIATE
- Make the changes immediately, while the database is running. IMMEDIATE is the default action, but it requires a database connection to be
effective.
This is a default clause when operating in the CLPPlus interface as well. IMMEDIATE need not be called when using CLPPlus processor.
- DEFERRED
- Make the changes only in the configuration file, so that the changes take effect the next time you reactivate the database.
Examples
Update database configuration on a multi-partition instance
This example demonstrates how to update database configuration parameter MAXAPPLS from 10 to 50 for a database named SAMPLE.
10 gilera 0
20 gilera 1
30 motobi 0
40 motobi 1
The user has created the SAMPLE database on the instance. The catalog partition for SAMPLE is on
member 10. Let us assume the user is logged on to system motobi
.
db2 update db cfg for sample using maxappls 50
db2 update db cfg for sample member 30 using maxappls 50
Usage notes
To view or print a list of the database configuration parameters, use the GET DATABASE CONFIGURATION command.
To reset all the database configuration parameters to the recommended defaults, use the RESET DATABASE CONFIGURATION command.
To change a database configuration parameter, use the UPDATE DATABASE
CONFIGURATION command. For example, to change the logging mode to archival logging
on a single-partition database environment containing a database called ZELLMART, use:
db2 update db cfg for zellmart using logarchmeth1 logretain
To check that the logarchmeth1 configuration parameter has changed, use:
db2 get db cfg for zellmart
For example, to change the logging mode to archival logging
on all
partitions (provided the registry variable DB2_UPDDBCFG_SINGLE_DBPARTITION is
set, by default, to NULL or FALSE) in a multiple-partitioned database environment
containing a database called zellmart
, use:
db2 update db cfg for zellmart using logarchmeth1 logretain
To check that the logarchmeth1 configuration parameter has changed on all database partitions, use:
db2_all ";db2 get db cfg for zellmart"
db2 update db cfg for zellmart member 30 using logarchmeth1 logretain
Optionally, you can leverage the SYSIBMADM.DBCFG
view to get
data from all partitions without having to use db2_all.
If you are working on a UNIX operating system, and you have the grep command, you can use the following command to view only the logarchmeth1 values:
db2_all ";db2 get db cfg for zellmart | grep -i logarchmeth1"
For more information about Db2 database configuration parameters and the values available for each type of database node, see the individual configuration parameter descriptions. The values of these parameters differ for each type of database node configured (server, client, or server with remote clients).
Not all parameters can be updated.
Some changes to the database configuration file become effective only after they are loaded into memory. All applications must disconnect from the database before this can occur. For more information aboutwhich parameters are configurable online and which ones are not, see summary list of configuration parameters.
db2 connect to sales
db2 update db cfg using sortheap 1000
db2 connect reset
If an error occurs, the database configuration file does not change. The database configuration file cannot be updated if the checksum is invalid. This might occur if the database configuration file is changed without using the appropriate command. If this happens, the database must be restored to reset the database configuration file.
Compatibilities
- DBPARTITIONNUM can be substituted for MEMBER, except when the DB2_ENFORCE_MEMBER_SYNTAX registry variable is set to ON.