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copied!<p><a href="http://optimizermagic.blogspot.com/2007/12/why-are-there-more-cursors-in-11g-for.html" rel="nofollow">Adaptive cursor sharing does not apply to LIKE predicates.</a></p> <p>If your procedure was first executed with a parameter such as <code>%</code>, Oracle cannot use certain index access methods for the predicate. Oracle could not obey your hint, and built a plan that was pretty good for <code>%</code> but horrible for everything else.</p> <p>One possible solution is to force Oracle to always hard-parse your query. I've used this solution, as explained by Dion Cho in <a href="https://forums.oracle.com/forums/thread.jspa?threadID=854605" rel="nofollow">this OTN thread</a>:</p> <pre><code>dbms_stats.set_table_stats('schema','DOC',num_rows=>null,no_invalidate=>false); </code></pre> <p>Hard-parsing will use extra CPU resources, but hopefully a better plan will more than make up for the difference. This solution will cause other, unrelated queries, to require a hard-parse. You may want to look at some other solutions mentioned in the referenced thread.</p> <p>Also, your <a href="http://docs.oracle.com/cd/E11882_01/server.112/e26088/sql_elements006.htm#BABHJBAJ" rel="nofollow">INDEX_COMBINE</a> hint may not be correct. There should not be a comma between the indexes. However, the hint syntax is poorly documented, and the hint parser will often work "partially". Your hint is probably evaluated as the equivalant of <code>/*+INDEX_COMBINE(attr)*/</code>, which may or may not work the way you want it to. You'll never know without the plans.</p> <p>There are good reasons to avoid hints, especially if you don't have convenient access to the explain plans.</p>

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