I’m trying to get the max and min date values in column C based on the (column A, column B) unique pair combinations.
Suppose I have a table like:
column_A column_B column_C A 1 2019-08-11 A 1 2018-11-12 A 1 2017-11-12 A 11 2020-03-03 A 11 2021-01-10 A 11 2021-02-02 B 2 2020-11-11 B 2 2020-12-12
The output I want to get is:
column_A column_B column_C A 1 2019-08-11 A 1 2017-11-12 A 11 2020-03-03 A 11 2021-02-02 B 2 2020-11-11 B 2 2020-12-12
My attempt query has been taking 20 mins to run with no output yet (just tried to get max date from column C for now):
SELECT column_A, column_B, column_C FROM table_name WHERE column_C IN ( SELECT MAX(column_C) FROM table_name GROUP BY column_A, column_B )
Advertisement
Answer
Just use two conditions:
select t.* from t where column_c = (select max(t2.colc) from table_name t2 where t2.column_A = t.column_A and t2.column_B = t.column_B ) or column_c = (select min(t2.colc) from table_name t2 where t2.column_A = t.column_A and t2.column_B = t.column_B ) ;