KB158164 - BUG: Optimistic Concurrency Error with DYNAMIC Cursors

Article ID: 158164

Article Last Modified on 10/16/2003

Microsoft SQL Server 6.5 Standard Edition
Microsoft Open Database Connectivity 2.5

This article was previously published under Q158164

SYMPTOMS

When you attempt to call the open Database Connectivity (ODBC) function SQLSetPos() multiple times with the SQL_UPDATE option on a DYNAMIC cursor, you may incorrectly receive the following error message:

szSqlState = "01S03", *pfNativeError = 16934,
szErrorMsg = "[Microsoft][ODBC SQL Server Driver][SQL Server]
Optimistic concurrency check failed, the row was modified outside of this cursor"

WORKAROUND

To work around this problem, switch to a keyset cursor on SQL Server 6.5 Service Pack 1 or later. To obtain SQL Server 6.5 Service Pack 1, see the following article in the Microsoft Knowledge Base:

154549 : INF: How to Obtain SQL Server 6.5 Service Pack 1

STATUS

Microsoft has confirmed this to be a problem in Microsoft SQL Server version 6.5 and Microsoft Open Database Connectivity version 2.5. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Error 16934 does not occur on very small tables (fewer than 100 rows). The error may occur on the second call to SQLSetPos, as in the following example:

   SQLSetStmtOption(hstmt, SQL_CONCURRENCY, SQL_CONCUR_VALUES);
   SQLSetStmtOption(hstmt, SQL_CURSOR_TYPE, SQL_CURSOR_DYNAMIC);
   SQLExecDirect(hstmt, "select command", SQL_NTS);
   SQLExtendedFetch(hstmt, SQL_FETCH_NEXT);
   SQLSetPos(hstmt, SQL_UPDATE, SQL_LOCK_NO_CHANGE);
   SQLExtendedFetch(hstmt, SQL_FETCH_NEXT);
   SQLSetPos(hstmt, SQL_UPDATE, SQL_LOCK_NO_CHANGE);

Keywords: kbbug kbinterop kbother kbusage KB158164