I have a table in MS Access which contains a list of module codes, example data sample:

MC31010

MC31020

MC31030

MC45678

MS21030

MS21020

MS32567 etc

Some modules are linked e.g. MC31010 and MC31020 are versions of MC31030 and MS21020 is a version of MS21030. If they are linked, the first 5 characters are the same.

I am trying to figure out a query which will list all modules which are linked (i.e. Have the same first five digits), and will discard any which are not linked. At the moment I cant see a way of doing this.please help! :(