Q119487: BUG: Time Value Converted to Datetime Using Access ODBC Driver

Article: Q119487
Product(s): Open Database Connectivity (ODBC)
Version(s): WINDOWS:1.0
Operating System(s): 
Keyword(s): kbBug kbISS
Last Modified: 27-JUL-2001

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The information in this article applies to:

- Microsoft Open Database Connectivity, version 1.0 
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BUG# ODBCDBASE: 2128 (1.01.1928)

SYMPTOMS
========

When a value of type time is converted and inserted into a column in a Microsoft
Access data source, defined as of type datetime, the converted value is
incorrectly interpreted by Microsoft Access.

For example, consider the following SQL statements, executed using ODBC calls:

     SQLAllocEnv(&henv);
     SQLAllocConnect (henv, &hdbc);
     SQLDriverConnect (hdbc, hwnd, "", 0,
       szConnStrOut,cbConnStrOutMax,&cbConnStrOut, SQL_DRIVER_PROMPT);
     SQLAllocStmt(hdbc, &hstmt);

You can use either prepared execution or direct execution.

Prepared Execution
------------------

     SQLPrepare(hstmt,"insert into test values(?)",SQL_NTS);

     //Bind the parameter, define rgbValue to be a TIME_STRUCT

     SQLBindParameter(hstmt,1,SQL_PARAM_INPUT, SQL_C_TIME,
                  SQL_TIMESTAMP,16,rgbValue,cbValueMax,
     pcbValue);

     //Set appropriate time values in the rgbValue

     //Execute the prepared statement
     SQLExecute(hstmt);

Direct Execution
----------------

     SQLExecDirect(hstmt,"insert into test values({t '10:10:10'})",SQL_NTS);

        SQLFreeStmt (hstmt, SQL_DROP);
        SQLDisconnect(hdbc);
        SQLFreeConnect(hdbc);
        SQLFreeEnv(henv);

When a select is executed on that table, the value returned is as expected, with
date part set to 0:

  0000-00-00 10:10:10

However, if the table is opened in Microsoft Access, the datetime field contains
time value as 12 AM with a date value of 12/30/9999.

WORKAROUND
==========

Use the timestamp value with a date part as well as time part when inserting or
doing the conversion.

For SQLBindParameter, change the fCType to SQL_C_TIMESTAMP and define rgbValue to
be TIMESTAMP_STRUCT, and set appropriate values in date and time parts of the
structure.

For SQLExecDirect, use escape clause for timestamp data instead of the escape
clause for time data.

     //Bind the parameter, define rgbValue to be a TIMESTAMP_STRUCT

     SQLBindParameter(hstmt,1,SQL_PARAM_INPUT,
     SQL_C_TIMESTAMP,SQL_TIMESTAMP,16,rgbValue,cbValueMax,pcbValue);

Direct Execution
----------------

     SQLExecDirect(hstmt, "insert into test values({ts '1990-01-01
     10:10:10'}",SQL_NTS)

This will set the date and time values correctly.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft Access ODBC driver
version 1.01.1928. We are researching this problem and will post new information
here in the Microsoft Knowledge Base as it becomes available.

Additional query words: 1.01.1928 ODBC MSVC VC++ DDD

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Keywords          : kbBug kbISS 
Technology        : kbAudDeveloper kbODBCSearch kbODBC100
Version           : WINDOWS:1.0
Issue type        : kbbug

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