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<TITLE>Oracles EXPLAIN PLAN</TITLE>
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<P>Slide 13 of 80</P>
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<!-- <UL>
<H2>Oracles EXPLAIN PLAN</H2>
</UL></P>
<P><UL>
<LI><H2>To generate a plan:
</H2>
<UL>
EXPLAIN PLAN SET STATEMENT_ID = 'Emp_Sal FOR
<BR><BR> SELECT ename, job, sal, dname
<BR> FROM emp, dept
<BR> WHERE emp.deptno = dept.deptno
<BR> AND NOT EXISTS
<BR> (SELECT * FROM salgrade
<BR> WHERE emp.sal BETWEEN losal AND hisal);
<UL>
<LI>
</UL></UL></UL><UL>
<LI><H2>That writes plan details into a table which can be queried to yield results like this:
</H2>
<UL>
ID PAR Query Plan
<BR><BR>--- --- --------------------------------------------------
<BR> 0 Select Statement Cost = 69602
<BR> 1 0 Nested Loops
<BR> 2 1 Nested Loops
<BR> 3 2 Merge Join
<BR> 4 3 Sort Join
<BR> 5 4 Table Access Full T3
<BR> 6 3 Sort Join
<BR> 7 6 Table Access Full T4
<BR> 8 2 Index Unique Scan T2
<BR> 9 1 Table Access Full T1</UL></UL></P>
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