Hi Simon,

I've work with a VFP front end to a postgresql back end that contains a boolean in the back end server. On the VFP side, you can store a 0 or 1 in a character field. For display you can use a drop down combo. The combo would contain two columns as follows

    yes  |  1
     no  |  0

A yes or a no would display in the grid, combobox, etc, but the control would have the second column bound to the cursor/table field. The user could drop down and select either yes or no and the control would insert a 1 or 0 into the cursor field. VFP's logical field is not SQL 92/99 compliant, so this problem is encountered with other back end databases like MS SQL, MySQL, DB2, etc. Maybe someone using one of the other SQL 92/99 compliant back end has a more eligant solution.

The method I describe to use with VFP is also used by other front ends like php, perl, etc. You might take a look at phpPgAdmin, as when you make a selection on a boolean in it when editing a row, you select a true or false from a drop down, but a 1 or 0 is what is actually inserted into the table.

the boolean ==> logical field mapping should not be a problem.

LelandJ