Dear heroes: There is a table tab_custinfo, and there are 500,000 records in the table. Now, I have established a cluster index for the fields A, B, C, D, E, the order, as follows: CREATE INDEX IDX_CUST1 ON TAB_CUSTINFO (A, B, C, D, E) When writing SQL statements, its WHERE condition As follows: Select * from tab_custinfo where a = ls_custid and c = ls_product_name; Excuse me, this index, is the performance phase difference with only a cluster index for field a, c? Thank you for your advice!
