Join & Group By - Column is invalid in the select list - sql

Question

I'm running a query to join 2 tables and then group the rows by 2 fields and select the rows with the min ID from these groups and I get an error. The joined table looks like:
+--------+---------+-----------------+-----------+-----------+
| ID | CODE | NAME | VRACHAR01 | VRACHAR02 |
+--------+---------+-----------------+-----------+-----------+
| 290861 | 1110896 | PRODUCT NAME XX | 001 | 706 |
| 290864 | 1110899 | PRODUCT NAME XX | 001 | 706 |
| 290865 | 1110900 | PRODUCT NAME XX | 003 | 721 |
| 290870 | 1110905 | PRODUCT NAME XX | 004 | 743 |
| 290871 | 1110906 | PRODUCT NAME XX | 004 | 743 |
| 290878 | 1110913 | PRODUCT NAME XX | 006 | 806 |
| 290879 | 1110914 | PRODUCT NAME XX | 007 | 807 |
| 290908 | 1110943 | PRODUCT NAME XX | 008 | 815 |
+--------+---------+-----------------+-----------+-----------+
If I run the script below to group the results by the last 2 fields I get an error:
Column 'A.CODE' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
SELECT
min(A.ID),
A.CODE,
A.NAME,
B.VARCHAR01,
B.VARCHAR02
FROM
PRODUCTS A
INNER JOIN
EXTRAS B
ON
A.ID = B.ID
WHERE
A.COMPANY = 1002
AND
A.TYPE = 50
GROUP BY
B.VARCHAR01,
B.VARCHAR02
Any help is appreciated.

Answer 1

If you want the min id, then you don't need other columns:
SELECT MIN(P.ID), E.VARCHAR01, E.VARCHAR02
FROM PRODUCTS P INNER JOIN
EXTRAS E
ON P.ID = E.ID
WHERE P.COMPANY = 1002 AND P.TYPE = 50
GROUP BY E.VARCHAR01, E.VARCHAR02;
Note that this replaces the meaningless table aliases with abbreviations for the table names.
If you want the entire row, then you can use window functions:
SELECT PE.*
FROM (SELECT P.*, E.VARCHAR01, E.VARCHAR02,
ROW_NUMBER() OVER (PARTITION BY E.VARCHAR01, E.VARCHAR02 ORDER BY P.ID ASC) as seqnum
FROM PRODUCTS P INNER JOIN
EXTRAS E
ON P.ID = E.ID
WHERE P.COMPANY = 1002 AND P.TYPE = 50
) PE
WHERE seqnum = 1;