Choose two. Which two are true about poorly performing SQL
Statements and their tuning in Oracle database instances?
A.SQL statements performing many physical I/Os can always have their正确答案BD
Performance improved by creating indexes. B.The solution that best optimizes one SQL statement can degrade the
Performance of others. C.SQL statements doing joins always do more physical I/O than single table
Queries. D.Poorly performing SQL statements can be tuned automatically by the Oracle
Server. E.SQL statements doing only logical reads never require tuning because they do
No physical I/O.
