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Martin Klier

usn-it.de

Oracle 11g and 12c Cardinality Feedback Leads to Hundreds of Child Cursors

Sometimes, advanced features can bring advanced problems. Seeing a project with hundreds of child cursors with a different execution plan each, is never a pleasure, but there has to be a reason. In fact, we are talking about the “USE_FEEDBACK_STATS” reason in v$sql_shared_cursor. Its meaning is: “A hard parse is forced so that the optimizer can reoptimize […]

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