Question

我在postgresql中返回值时遇到麻烦，我创建了这样的函数（EDITED）：

CREATE OR REPLACE FUNCTION GetComissionamento(pv varchar(50))
RETURNS SETOF tb_comissionamentos AS
$$
BEGIN
SELECT com.* FROM tb_vendas as vendas 
 INNER JOIN tb_pagamentos as pg on vendas.id_venda = pg.id_venda
 INNER JOIN tb_comissionamentos as com on vendas.id_venda = com.id_venda 
    AND com.id_pagamento = pg.id_pagamento
 WHERE id_venda_imobiliaria = pv;
END
$$
LANGUAGE plpgsql;

我想在表格tb_comissionamento上返回数据，如查询所示。我该怎么办？当我调用该函数时，我收到了错误消息：

ERROR:  query has no destination for result data
HINT:  If you want to discard the results of a SELECT, use PERFORM instead.

Answer 1

这很糟糕。

这应该是VIEW而不是功能

像这样，

CREATE VIEW GetComissionamento AS 
SELECT com.* FROM tb_vendas as vendas 
     INNER JOIN tb_pagamentos as pg on vendas.id_venda = pg.id_venda
     INNER JOIN tb_comissionamentos as com on vendas.id_venda = com.id_venda 
        AND com.id_pagamento = pg.id_pagamento;

然后（其中$ pv是你的价值），

SELECT *
FROM GetComissionamento
WHERE id_venda_imobiliaria = $pv;

如果您打算使用sql而不是plpgsql

像这样，

CREATE FUNCTION GetComissionamento(varchar(50))
RETURNS tb_comissionamentos AS $$
SELECT com.* FROM tb_vendas as vendas 
 INNER JOIN tb_pagamentos as pg on vendas.id_venda = pg.id_venda
 INNER JOIN tb_comissionamentos as com on vendas.id_venda = com.id_venda 
    AND com.id_pagamento = pg.id_pagamento
 WHERE id_venda_imobiliaria = $1;
$$ LANGUAGE SQL;

如果您打算将其作为plpgsql使用RETURN QUERY。

像这样，

CREATE OR REPLACE FUNCTION GetComissionamento (pv varchar(50))
RETURNS tb_comissionamentos AS $$
BEGIN
  RETURN QUERY
     SELECT com.* FROM tb_vendas as vendas 
     INNER JOIN tb_pagamentos as pg on vendas.id_venda = pg.id_venda
     INNER JOIN tb_comissionamentos as com on vendas.id_venda = com.id_venda 
        AND com.id_pagamento = pg.id_pagamento
     WHERE id_venda_imobiliaria = pv;
  -- error checking or whatever
  RETURN;
END;
$$ LANGUAGE plpgsql;

Answer 2

是的，得到了错误，忘了返回查询

class UserService { d: UserGroupDao =>
  val dao = d
  def read(userId: String): Future[Option[User]] = dao.readUser(userId)
}

class GroupService { svc: UserService =>
  def createGroup(group: Group): Future[Either[String, String]] = {
    svc.read(group.ownerId) map {
      case Some(_) => svc.dao.createGroup(group)
      case None => Left("Invalid User!")
    }
  }
}

使用plpgsql的`RETURN SETOF`返回一个带连接的简单查询

2 个答案: