answer for https://stackoverflow.com/questions/62027855/compare-value-in-sql-column-and-output-accordingly

notes.txt

for example if you have

Id State1  State2
1  1        DE
2  1        GA
3  1        AL
4  1        DC
5  1        FG
6  1        KG
7  1        PM
9  2        LM
9  2        Nk

Then

SELECT State1, COUNT(*) AS COUNT, LISTAGG(CASE WHEN RN > 5 THEN State2 ELSE NULL END, ', ') AS STATES
FROM (SELECT *,
             ROW_NUMBER() OVER (PARTITION BY State1 ORDER BY ID) as RN
      FROM TABLE1
) AS X
GROUP BY State1