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分组与亚音速3

grouping group-by subsonic3 subsonic

0

Andreas · 技术社区 · 16 年前

Id   Group   Priority
 1       1         0
 2       2         0
 3       3         0
 4       2         1
 5       1         1
 6       2         2
 7       3         1

Id   Group   Priority
 5       1          1
 6       2          2
 7       3          1

sql看起来像这样:

SELECT *
FROM   GroupPriority
WHERE  (Priority =
                  (SELECT  MAX(Priority)
                   FROM    GroupPriority
                   WHERE   (Group = GroupPriority.Group)))

1 回复 | 直到 16 年前

1

0

Andreas 16 年前

    var group_query = new Query<GroupPriority>(provider);
    var items = from gp in group_query
                where gp.Priority == 
                    (from gp_sub in group_query
                     where gp_sub.Group == gp.Group
                     select gp_sub.Priority).Max()
                select gp;