Unable to Retrieve UTF-8 Accented Characters from Access via PDO_ODBC

When attempting to retrieve data from an Access database using PHP ODBC, specifically via PDO_ODBC, non-standard characters may not be imported correctly, and can cause issues such as displaying question marks in place of special characters.

Understanding the Issue

The issue stems from the fact that the Access ODBC driver does not transmit data in UTF-8 format, even though the database may store data in Unicode. Consequently, when the ODBC driver returns the text, it is encoded in a non-standard format, often Windows-1252. This encoding is not fully compatible with UTF-8, leading to display problems in browsers and PHP.

Partial Solutions

Some common attempts to address the issue include using mb_convert_encoding() to convert from Windows-1252 to UTF-8. However, this approach does not completely solve the problem, as characters outside of Windows-1252 may still be misrepresented.

Complete Solution

To fully address the issue and handle UTF-8 data effectively, it is necessary to employ COM with ADODB Connection and Recordset objects. COM (Component Object Model) and ADODB (ActiveX Data Objects) enable direct interaction with the Access database and allow for proper handling of UTF-8 data.

By creating a COM object and setting the code page to UTF-8 using CP_UTF8, the database connection can be established with the correct language encoding. The ADODB Recordset object can then be used to retrieve data from the database, ensuring that the characters are maintained in their original format and displayed correctly in both browsers and PHP.