You want to capture column group usage and gather extended statistics for better cardinality estimates for the CUSTOMERS table in the SH schema. Examine the following steps: 1. Issue the SELECT DBMS_STATS.CREATE_EXTENDED_STATS (‘SH’, ‘CUSTOMERS’) FROM dual statement. 2. Execute the DBMS_STATS.SEED_COL_USAGE (null, ‘SH’, 500) procedure. 3. Execute the required queries on the CUSTOMERS table. 4. Issue the SELECT DBMS_STATS.REPORT_COL_USAGE (‘SH’, ‘CUSTOMERS’) FROM dual statement. Identify the correct sequence of steps.()
- A、3,2,1,4
- B、2,3,4,1
- C、4,1,3,2
- D、3,2,4,1
正确答案:B
答案解析:有
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