Task: Text to Code
Input (English): Step 1: find the Fname, Sex of Student table.
Step 2: For each row in Has_Allergy table, find corresponding rows in Allergy_Type table and in Student table.
Step 3: find Fname, Sex of the results of step 2 whose Allergy_Type's Allergy equals Cat.
Step 4: show the rows that are in the results of step 1 but not in the results of step 3
Output (English): SELECT T1.Fname , T1.Sex FROM Student AS T1 EXCEPT SELECT T1.Fname , T1.Sex FROM Allergy_Type AS T2 JOIN Has_Allergy AS T3 ON T2.Allergy = T3.Allergy JOIN Student AS T1 ON T3.StuID = T1.StuID WHERE T2.Allergy = "Cat"