Question

我遇到了必须用来返回多行的数据类型和方法的问题。我在数据库（存储过程）中有一个函数，它执行以下操作：

SELECT *
FROM table
INNER JOIN some_table ON value = value
INNER JOIN some_tabl a ON value = value
INNER JOIN some_tabl ON value = value
WHERE table.id= 20

此函数的输出给出1：n行。如何返回多行？如果调用这样的函数：

SELECT * FROM functioname()

它不起作用，因为我必须给列名。当我尝试在postgres中使函数输出参数正确时，它一直给我错误。有人可以帮我弄这个吗？非常感谢

Answer 1

function vs stored procedure in postgresql

  create table test(a int, b varchar(50));
  create table test1(a int, b varchar(50));

  DROP FUNCTION some_function(in int);

  CREATE OR REPLACE FUNCTION some_function(in int)
   RETURNS TABLE(a int, b character varying, c int, d character varying) AS
  $BODY$

  DECLARE
      some_input ALIAS FOR $1;


  BEGIN
    RETURN QUERY SELECT * from test a inner join test1 b on a.a = b.a where a.a = some_input;
  END$BODY$

   LANGUAGE plpgsql VOLATILE
   COST 100
   ROWS 1000;
  ALTER FUNCTION some_function(in int)
   OWNER TO postgres;
  COMMENT ON FUNCTION some_function(in int) IS 'FUNCTION JUST FOR TEST';

  SELECT * FROM some_function(1);

返回多行postgres / sql语言

1 个答案: