PRB: "Error Retrieving Record" with SQL Statement in Open()

The information in this article applies to:

• The Microsoft Foundation Classes (MFC), included with: Microsoft Visual C++, 32-bit Edition, versions 4.0, 4.1, and 4.2

SYMPTOMS

The following exception is thrown in a MFC database application that specifies a SQL statement in the call to CRecordset::Open():

   Error retrieving record

The following debug messages are also displayed in the debug window if database tracing is on:

   Warning: <type name> converted from SQL type <type number>.
   Error: fetching row from server.
   Error in row
   Error in assignment on column number <#> (<column name>)

CAUSE

The Microsoft Access ODBC driver returns these errors if a column is bound to an unsupported data type. The error message returned is specific to the 32-bit Microsoft Access ODBC driver that ships with Visual C++ 4.x.

MORE INFORMATION

One reason for this error is that a developer has specified a SQL statement as the second argument for the CRecordset::Open() function. In this case, the columns listed in the SQL SELECT statement must match the order by which the RFX functions are called in the CRecordset's DoFieldExchange(). The first RFX function maps to the first column returned in the recordset, the second RFX function maps to the second column, and so on. The exception is thrown when the RFX functions are out of order. Paying attention to the exception can save developers a lot of debugging time.

A different error message can be returned for other drivers, and is documented in the following KB article.

    ARTICLE-ID: Q123977
    TITLE:      PRB: "Unexpected column data types were returned from
                query"