dbExpress TSQLQuery Issue

2006-06-13 08:57:53 AM
I am running several queries to check temperatures, but I only want
temperatures for specific thermometors. I have run several queries,
all getting valid results. When I run a compound query, I get an
Access Violation Exception.
The query looks like this (T is a thermometor, F is Farenheit
Select T, F, max(dateTime_stamp)
from temps
where T in (select T from therms where Type='DAT')
Group by T
Is this an invalid query using dbExpress??