We have a very complicated SQL grammar (e.g. 600 data types, e.g. hundreds of
functions)...

I would like to make a tool something like Intellisense with the VC++ Visual
Studio help so that as people are typing their SQL statement into the edit
control, they get help on what is expected.

So when they type in

SELECT RMSERROR(
they get prompted for:
<<NUMERIC VALUE>>
)

Any hints as to the best way to proceed?