Sun River
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 A SQL profile is sort of like gathering statistics on A QUERY - which involves many
tables, columns and the like....
In fact - it is just like gathering statistics for a query, it stores additional
information in the dictionary which the optimizer uses at optimization time to determine
the correct plan.  The SQL Profile is not "locking a plan in place", but rather giving
the optimizer yet more bits of information it can use to get the right plan.
posted on 2009-01-28 11:14 Sun River 阅读(228) 评论(0)  编辑  收藏 所属分类: JDBC