[egenix-users] mxODBC and Microsoft SQL Server 2000

[nwingfield at che-llp.com]

We are having trouble with mxODBC and Microsoft SQL Server 2000, when two
or more people run the same query at the same time.  This trouble is easily
reproduced by opening two browser windows and loading a page that executes
a lengthy SQL query in both windows simultaneously.  Exhibit A shown below
is the most common, but Exhibit B is not hard to reproduce under the same
circumstances.  Exhibits C and D are also fairly common, and though not
directly SQL-related, suggest incomplete or corrupted recordsets.
Sometimes one window will successfully load the page; sometimes neither
will.  Never do both windows successfully load the page simultaneously.  I
would appreciate any suggestions.

EXHIBIT A
Error Type: ProgrammingError
Error Value: ('HY000', 0, '[Microsoft][ODBC SQL Server Driver]Connection is
busy with results for another hstmt', 5911)

EXHIBIT B
Error Type: InterfaceError
Error Value: ('HY010', 0, '[Microsoft][ODBC SQL Server Driver]Function
sequence error', 4350)

EXHIBIT C
No input was provided for vendor_ids (this is a ZSQLMethod error)

EXHIBIT D
Error Type: IndexError
Error Value: tuple index out of range

Some environmental variables to consider:
- We do not use stored procedures
- This occurs with every permutation of connection pooling options, within
both Zope and the Windows ODBC Administrator
- This does not occur under ZODBCDA
- Connected database: Microsoft SQL Server, 08.00.0194
- ODBC driver: SQLSRV32.DLL, 03.80.0194