1、userid是分组列
3、查询以userid分组,以createtime排序,每组的第一条记录
4、SELECT *FROM ( SELECT ROW_NUMBER() O外狒芙梨VER (PARTITION BY t.useridORDER BY t.createtime DES潮贾篡绐C) AS rn, t.* FROM t_book t)WHERE rn = 1
oracle不使用group by 分组过滤数据
时间：2024-10-31 19:19:261、userid是分组列
3、查询以userid分组,以createtime排序,每组的第一条记录
4、SELECT *FROM ( SELECT ROW_NUMBER() O外狒芙梨VER (PARTITION BY t.useridORDER BY t.createtime DES潮贾篡绐C) AS rn, t.* FROM t_book t)WHERE rn = 1