We’ll add to this page over time, as we use MapInfo Professional in our work, and when we get an enquiry from a client about a problem they’re trying to solve.

Help Guide

Looking for a complete reference for all available expressions? Click on the Help button inside any MapInfo dialog box (or Help > MapInfo Professional Help Topics) to open up the Help box.

Alternatively, you can access the Help box from outside MapInfo by creating a desktop shortcut for (or navigating and double-clicking on) ”C:\Program Files\MapInfo\Professional\Mapinfow.chm”.

Type the word ‘string’ into the search box, hit Enter, then select ‘String Functions’ from the topic list.

Mid$

Say you want to update a field to cut off the first 9 characters of the all the values in that field. You basically need to perform a substring kind of command, which in other SQL languages, is a standard command. In MapInfo however, you need to think about it in terms of returning the middle part of the string. Try this:

update TableName set FieldName = Mid$(FieldName,10,99)

This will return a value that starts at the 10th character, and continues for 99 characters after that. So if the original value was ‘abcdefghijklmnopqrstuvwxyz’, the new value would be ‘jklmnopqrstuvwxyz’.