FIX: Many ISNULLs Within an Expression May Cause Access Violation

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Article ID: 247134 - View products that this article applies to.
This article was previously published under Q247134
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BUG #: 55405 (SQLBUG_70)
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A T-SQL Query with an expression having many operands calling the ISNULL System Function may cause a handled Access Violation (AV) for the connection. The following error message occurs:
ODBC: Msg 0, Level 19, State 1 [Microsoft][ODBC SQL Server Driver][SQL Server]SqlDumpExceptionHandler: Process 7 generated fatal exception c0000005 EXCEPTION_ACCESS_VIOLATION. SQL Server is terminating this process.

Connection Broken


Use the COALESCE System function instead of ISNULL.


Microsoft has confirmed this to be a problem in SQL Server 7.0. This problem has been corrected in U.S. Service Pack 2 for Microsoft SQL Server 7.0. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
254561 INF: How to Obtain Service Pack 2 for Microsoft SQL Server 7.0 and Microsoft Data Engine (MSDE) 1.0
For more information, contact your primary support provider.


Both string and numeric expressions that have a lot of operands with calls to ISNULL may cause the Access Violation.


Article ID: 247134 - Last Review: October 22, 2013 - Revision: 2.1
  • Microsoft SQL Server 7.0 Standard Edition
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