Analyzing Materialized Views for Fast Refresh

The article will describe how materialized views can be analyzed and optimized to ensure they can be FAST REFRESHED, through this way refresh time will reduced from more than 5hours to less than 1hour.

The tools used to perform the FAST REFRESH analysis are:

– DBMS_MVIEW

– MV_CAPABILITIES_TABLE

The Oracle provided DBMS_MVIEW.explain_mview procedure is used to analyze each of the existing materialized views FAST REFRESH capabilities and write the results to the MV_CAPABILITIES_TABLE.

The MV_CAPABILITIES TABLE is created in the owner’s schema by running the following Oracle 9i script:

SQL> @$ORACLE_HOME/rdbms/admin/utlxmv.sql

Steps:

– Created the necessary materialized view logs for each of the master tables making sure to include all columns referenced in any of the materialized view aggregations along with the ROWID, SEQUENCE, and INCLUDING NEW VALUES clauses based on the Oracle 9i documentation FAST REFRESH requirements.

– Created materialized views including the REFRESH FORCE ON DEMAND option, in order to prepare for the detailed analysis of the respective FAST REFRESH

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