Altering a Dbslice

To alter a dbslice, add dbspaces to it. You can either add dbspaces to a dbslice on the same coservers on which they were created or expand a dbslice to another coserver. These new dbspaces are not automatically visible to the existing tables in the dbslice. Use the SQL statement ALTER FRAGMENT to refragment the tables to enable them to use the new dbspaces in the dbslice. After you alter the dbslice, you can store new tables in either the new or old dbspaces.

Suppose you add coservers eds.4 and eds.5 to the dbslice dbsl that you created in the previous example. (See Creating Dbslices.) To expand the dbslice to the new coservers, use the following command:

% onutil
ALTER DBSLICE dbsl ADD DBSPACE
FROM COGROUP eds.%r(4..5)
CHUNK '/dev/dbsl_45' SIZE 2048;

This command creates two 2048-kilobyte dbspaces in the dbslice, one each on coservers eds.4 and eds.5. If this dbslice also contains a logslice, use the onutil ALTER LOGSLICE command to add logical logs to the logslice. The above example assumes that one coserver exists on each node. For more information on onutil, see the utilities chapter in the IBM Informix: Administrator's Reference.