Question

给出这两个示例表：

authors(
  id SERIAL PRIMARY KEY,
  name VARCHAR(60) UNIQUE,
  profession VARCHAR(30)
)

posts(
  id SERIAL PRIMARY KEY,
  text TEXT,
  author_id INT REFERENCES authors(id)
)

作者表有所有作者，但现在我正在尝试填充posts表，我有一组数据，基本上有一个带有作者姓名的帖子，但我想查询author_id这样我就可以按如下方式插入到引号表中：

INSERT INTO posts(text, author_id) VALUES(
  /* 
     pseudo broken-code
     SELECT post, author FROM posts_temp (where all of the data temp resides),
     SELECT id FROM authors WHERE authors.name = author.name (obviously this is wrong, but the idea is getting the id from the authors table that matches the author name from the selection above)
  */

)

Answer 1

INSERT语句可以使用SELECT语句返回的行作为插入数据的源。因此，从SELECT和posts_temp构建相应的authors语句，然后就完成了：

INSERT INTO posts(text, author_id)
  SELECT pt.post, a.id
  FROM posts_temp pt
  JOIN authors a ON a.name = pt.author;

Answer 2

DECLARE @InsertedIds TABLE（AID BIGINT）插入作者（身份证，姓名，专业） OUTPUT INSERTED.Id INTO @InsertedIds SELECT @ Id，@ name，@ professional

INSERT INTO帖子（id，text，author_id） SELECT @ Id，@ text，AID FROM @InsertedIds

从另一个表获取ID后插入表

2 个答案: