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

Question: What team 1 has a team 2 of universidad nacional?
SQL: SELECT "team_1" FROM concachampions_preliminary WHERE "team_2" = 'universidad nacional'

Question: What team 2 has a team 1 of harbour view?
SQL: SELECT "team_2" FROM concachampions_preliminary WHERE "team_1" = 'harbour view'

Question: What's the 2nd leg for team 2 san francisco?
SQL: SELECT "2nd_leg" FROM concachampions_preliminary WHERE "team_2" = 'san francisco'

Question: What's the 1st leg of team 1 alajuelense?
SQL: SELECT "1st_leg" FROM concachampions_preliminary WHERE "team_1" = 'alajuelense'