Suppose I have a table like this:
+---+---+---+---+---+ |G1 |G2 |G3 |G4 | V | +---+---+---+---+---+ | A | B | C | D | 2 | | E | F | G | H | 4 | | C | D | A | B | 2 | | E | F | G | H | 3 | | E | I | G | L | 7 | +---+---+---+---+---+
G1 and G3 are VARCHAR types, G2 and G4 are INT types
If I do a simple GROUP BY on G1..G4, I get:
SELECT G1,G2,G3,G4,SUM(V) as V FROM Table GROUP BY G1, G2, G3, G4;
+---+---+---+---+---+
|G1 |G2 |G3 |G4 | V |
+---+---+---+---+---+
| A | B | C | D | 2 |
| E | F | G | H | 7 |
| C | D | A | B | 2 |
| E | I | G | L | 7 |
+---+---+---+---+---+
I want to know if it is possible to do aggregation on inverted values G1, G2 <-> G3, G4. The result I want is this:
+---+---+---+---+---+ +---+---+---+---+---+ |G1 |G2 |G3 |G4 | V | |G1 |G2 |G3 |G4 | V | +---+---+---+---+---+ +---+---+---+---+---+ | A | B | C | D | 4 | 或 | C | D | A | B | 4 | | E | F | G | H | 7 | | E | F | G | H | 7 | | E | I | G | L | 7 | | E | I | G | L | 7 | +---+---+---+---+---+ +---+---+---+---+---+
I tried getting the reversed rows but I still can't aggregate on them due to duplicates. My test query is:
SELECT DISTINCT *
FROM Table t1
JOIN Table t2 on t1.G1 = t2.G3 and t1.G2=t2.G4 and t1.G3=t2.G1 and t1.G4=t2.G2
+---+---+---+---+---+---+---+---+---+---+
|G1 |G2 |G3 |G4 | V |G1 |G2 |G3 |G4 | V |
+---+---+---+---+---+---+---+---+---+---+
| A | B | C | D | 2 | C | D | A | B | 2 |
| C | D | A | B | 2 | A | B | C | D | 2 |
+---+---+---+---+---+---+---+---+---+---+
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If I understand correctly, reverse the order of the columns so that A B C D corresponds to C D A B.
select case when(g1 > g3) then g3 else g1 end G1, case when(g1 > g3) then g4 else g2 end G2, case when(g1 > g3) then g1 else g3 end G3, case when(g1 > g3) then g2 else g4 end G4, sum(V) from tbl group by case when(g1 > g3) then g3 else g1 end, case when(g1 > g3) then g4 else g2 end, case when(g1 > g3) then g1 else g3 end, case when(g1 > g3) then g2 else g4 enddb<>fiddle