SQL 语句的效率比较
<div id="cnblogs_post_body">低效: TOP 1 高效: MAX低效: SELECT &hellip; FROM DEPT WHERE SAL * 12 > 25000; 高效: SELECT &hellip; FROM DEPT WHERE SAL >25000/12;
低效: SELECT * FROM EMP WHERE DEPTNO >3 高效: SELECT * FROM EMP WHERE DEPTNO >=4
低效:SELECT * FROM LOCATION WHERE LOC_ID = 10 OR LOC_ID = 20 OR LOC_ID = 30
高效:SELECT * FROM LOCATION WHERE LOC_IN IN (10,20,30);
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