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  6. Case: Adjusting the Partial Clustering Key

Case: Adjusting the Partial Clustering Key

Symptom

Information on the EXPLAIN PERFORMANCE at a site is as follows: As shown in the red boxes, two performance bottlenecks are scan operations in a table.

Optimization Analysis

After further analysis, we found that the filter condition acct_id ='A012709548':: bpchar exists in the two tables.

Try to add the partial clustering key in the acct_id column of the two tables, and run the VACUUM FULL statement to make the local clustering take effect. The table performance is improved.