Error: Invalid expression in the select list (not contained in either an aggregate function or the GROUP BY clause)

Question

I am using Firebird SQL. The below mentioned query returns 4 rows as shown in the figure.

    SELECT a.EPS_ID,b.C_NAME,c.AY_YR_NAME,d.S_NAME,e.E_NAME
FROM 
          


        

Answer 1

Learn to use proper, explicit JOIN syntax.

Your problem is that all unaggregated columns need to be in the GROUP BY:

SELECT a.EPS_ID, MAX(b.C_NAME) AS XT, c.AY_YR_NAME, d.S_NAME, e.E_NAME
FROM TBLEXAMPLANNER_S_MSB a JOIN 
     TBLCLASS_MSB b
     ON a.EPS_CLASS_ID = b.C_ID JOIN
     TBLACADEMICYEAR_MSB c
     ON a.EPS_SESSION_ID = c.AY_ID JOIN
     TBLSUBJECTS_MSB d
     ON a.EPS_SUB_ID = d.S_ID JOIN 
     TBLEXAMTYPE_MSB e
     ON a.EPS_PE_ID = e.E_ID
GROUP BY a.EPS_ID, c.AY_YR_NAME, d.S_NAME, e.E_NAME;

Note: I would also recommend that you use table abbreviations for table aliases. So, ep for TBLEXAMPLANNER_S_MSB instead of a. Arbitrary table aliases make the query hard to follow.