Read and write the settings only from the preferences dialog.
Remove all the copies of some settings which were stored in nearly every
dialog class individually.
Simplify the settings dialog code by removing all those not really
needed slots.
Store the data of a DB cell in a QByteArray, i.e. a binary data type,
instead of putting it in a QString, thus converting it to a UTF8 string.
Rewrite the reading and writing of DB cells to correctly handle binary
data containing 0x00 bytes.
Change the edit dialog to actually do all the data checks etc. on a
currently invisible QHexEdit widget instead of a QTextEdit.
All these changes combined make it possible to actually store binary
data without it being corrupted. You can for example import pictures
now, export them and actually open the exported file. So this is an
improvement.
Rewrite the dialog to export tables as CSV file using Qt Designer.
Move the entire export functionality to this dialog instead of
generating the file in the main window.
Add some options for the user to change the layout of the CSV file.