The Update Synchronizer and some of the Oracle features that

MDM Registry Edition

uses work only with the cost-based optimizer (CBO). If you have optimized the existing applications to use the rule-based optimizer (RBO), you can enable CBO only for

MDM Registry Edition

.

To enable CBO for

MDM Registry Edition

, set the

OPTIMIZER_MODE

initialization parameter to RULE and collect statistics for the USTs. The existing applications continue to use RBO, and when

MDM Registry Edition

accesses the USTs,

MDM Registry Edition

specifies the CHOOSE hint. The CHOOSE hint causes the optimizer to choose between RBO and CBO based on the presence of statistics. If statistics exist for any of the USTs,

MDM Registry Edition

uses the CBO.