Critical Vulnerability Information Vulnerability ID: IZ58417 Description: In V9.5, queries may compile infinitely if the following conditions are met: - At least two UNION ALLs are indirectly connected through one or more table joins - One of the UNION ALLs has a correlated column joining to a table or another UNION ALL - The forced application of this functionality in V9.1 is invalid Affected Users: All customers with UNION ALL views containing correlated predicates Issue Description: If a UNION ALL view contains conflicting correlated predicate branches, the query may compile infinitely Recommended Fix: Upgrade to DB2 Version 9.5 Fix Pack 6a Workaround: Set CURRENT OPTIMIZATION LEVEL to 0 or 1 Fixed Versions: - DB2 Version 9.5 Fix Pack 7 (Linux, UNIX, Windows) - DB2 Version 9.5 Fix Pack 10 (Linux, UNIX, Windows) - DB2 Version 9.5 Fix Pack 6a (Linux, UNIX, Windows) - DB2 Version 9.5 Fix Pack 9 (Linux, UNIX, Windows) - DB2 Version 9.5 Fix Pack 8 (Linux, UNIX, Windows) Status: Closed Product: DB2 Linux, UNIX and Windows Software Version: 9.5.0 Submission Date: August 14, 2009 Closure Date: May 25, 2010 Last Modified Date: August 25, 2023