Optimize Joins and Query Plan Changes

Joins and Query Plans Details of the article can be viewed at ask Tom Below are two queries posted by a user on askTom site. </pre>1) SELECT distinct D.deptno, D.dname FROM dept D, emp E WHERE E.deptno = D.deptno ORDER BY D.deptno; 2) SELECT D.deptno, D.dname FROM dept D WHERE EXISTS ( SELECT 1 FROM [...]

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