> I get newly different displays of datetime values using MySQL database. The
> Data Viewer shows the values correctly, not so the DateTimePicker and
> DBGrid.
>
> The value format is correct when fresh entered in the DateTimePicker,
> changes after saving and reloading - in the Data Viewer doesn't change
> anything. Is this related to DB-settings (which ones)? It seems that the DB
> reports them well (Data Viewer).
>
> Also there is an issue saving the data: sometimes it works, mostly not,
> without any Firebug error output.
>
> Changes made recently: Upgrade of MySQL to version 5.1.

You may need to do some coercion of the date data in your select query from MySQL as the DBGrid in particular relies upon string data and has no autoconversion of datatypes. The Datetime picker can have a multitude of datetime formats which are set as a property. I recommend you trackl down the source code or rather the documentation for that control from the original developer. The PDF doc does not come with the VCL for PHP.

http://www.dynarch.com/projects/calendar/old/

Conversely when saving the data you may have to cast the data or format the date data but this depends entirely on whether you are using tables views or stored procedures to update the data.

If you need to debug SQL issues like failed updates and incorrect parameters or mangled SQL and you dont have a SQL monitor like Toad for MySQL then turn on debuging in the Database component property "Debug". I doubt Firebug will help you.

These kinds of value/property issues should be readily solvable by setting breakpoints in the PHP debugger when you are making assignments to and from the control display value. Have you not tried that approach?