select ... from t1, t2

背景：我现在有两个表，t1表的字段为t1.impression_id, t1.Label, t2表的字段为t2.prediction_score, t2.impression_id,现在我需要将这两个表合并到一个表中

思考：观察，这两个表的外主键为impression_id，接着，我们来拼接一下
代码实现：

select t1.impression_id , t1.label, t2.prediction_score from t1, t2 where t1.impression_id = t2.impression_id