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@ -1,4 +1,4 @@ |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.72 2009/06/17 21:58:49 tgl Exp $ --> |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.73 2010/02/24 14:10:24 alvherre Exp $ --> |
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<chapter id="mvcc"> |
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<title>Concurrency Control</title> |
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@ -1080,7 +1080,7 @@ SELECT pg_advisory_lock(id) FROM foo WHERE id = 12345; -- ok |
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SELECT pg_advisory_lock(id) FROM foo WHERE id > 12345 LIMIT 100; -- danger! |
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SELECT pg_advisory_lock(q.id) FROM |
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( |
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SELECT id FROM foo WHERE id > 12345 LIMIT 100; |
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SELECT id FROM foo WHERE id > 12345 LIMIT 100 |
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) q; -- ok |
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</screen> |
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In the above queries, the second form is dangerous because the |
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