I had some difficulty in getting a lookup column in the grid and, after lots of searches pointing to convoluted solutions, I came across the following 2 pages, which gave me the info I needed to solve the problem.
Defining a Lookup List Column
Defining a lookup field
In a nutshell, you need to create a lookup field in the TSqlQuery (or whatever query type you use).
You then add a new field in the grid control and link it to the lookup field you created in the query.
Using this method means that you must specify the UPDATE and INSERT SQL (just in case you used to rely on what FreePascal/Delphi generated).
A lookup field is created in the CrewMembers query, as show below
The CrewMembers table contains only the CrewID, not the name.
LookupKeyField= The name of the key field in the Crew table that I will link to via my CrewID
keyFields=The name of the key field in my table/grid (in this case, CrewID)
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