I have two tables:
labusers
fields: userid (key), email, firstname, lastname... etc
labresults
fields: userid (key), surveyid (key)... etc survey info
I need to select email from labusers when their userid does not exist in labresults for a specified surveyid. (Basically, list the emails for all who have not taken a given survey)
Any suggestions?
labusers
fields: userid (key), email, firstname, lastname... etc
labresults
fields: userid (key), surveyid (key)... etc survey info
I need to select email from labusers when their userid does not exist in labresults for a specified surveyid. (Basically, list the emails for all who have not taken a given survey)
Any suggestions?