Table: ehf_champs_league
Columns: team_1
agg
team_2
1st_leg
2nd_leg

Question: Which team 1 has vfl gummersbach as team 2?
SQL: SELECT "team_1" FROM ehf_champs_league WHERE "team_2" = 'vfl gummersbach'

Question: What is the 2nd leg that has 31-37 as the 1st leg?
SQL: SELECT "2nd_leg" FROM ehf_champs_league WHERE "1st_leg" = '31-37'

Question: Which team 1 has cbm valladolid as team 2?
SQL: SELECT "team_1" FROM ehf_champs_league WHERE "team_2" = 'cbm valladolid'

Question: What 2nd leg has rk gold club kozina as team 1?
SQL: SELECT "2nd_leg" FROM ehf_champs_league WHERE "team_1" = 'rk gold club kozina'

Question: What 1st leg has 52-70 as the agg.?
SQL: SELECT "1st_leg" FROM ehf_champs_league WHERE "agg" = '52-70'