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sqlkoram-子选择上的join,但如何指定别名?

sqlkorma korma clojure

1

Freid001 · 技术社区 · 6 年前

我要为此查询中的子选定对象指定别名:

(->
  (korma/select* table_a)
  (korma/join
      (korma/subselect table_b
                       (korma/fields :id (korma/raw "COUNT(*) AS count"))
                       (korma/group :id)
   (= :id :id))

这是我要创建的SQL:

SELECT * FROM table_a LEFT JOIN (SELECT id, COUNT(*) AS count FROM table_b GROUP BY id) AS b b.id = id;

但目前,sql korma刚刚生成:

SELECT * FROM table_a LEFT JOIN (SELECT id, COUNT(*) AS count FROM table_b GROUP BY id) id = id;

1 回复 | 直到 6 年前

1

0

Freid001 6 年前

我需要将子选择定义为一个单独的实体,如下所示:

(korma/defentity sub-select
             (korma/table (korma/subselect table_b
                                           (korma/fields :id(korma/raw "COUNT(*) AS count"))
                                           (korma/group :id)) :b))

(->
  (korma/select* table_a)
  (korma/join sub-select (= :b.id :id)))

生成以下查询:

SELECT * FROM table_a LEFT JOIN (SELECT id, COUNT(*) AS count FROM table_b GROUP BY id) a.id = id;