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WITH t(team) AS
(
SELECT '1' FROM dual UNION ALL
SELECT '2' FROM dual UNION ALL
SELECT '1' FROM dual UNION ALL
SELECT '2' FROM dual UNION ALL
SELECT '3' FROM dual
)
select count(team) from (select team, COUNT(team) as countTeam from t group by team) where countTeam = 1
| COUNT(TEAM) |
|---|
| 1 |