Question

我正在设计一个使用几个游标的函数，我是Postgres的新手，所以我不知道我正在制作的任何小的语法问题。我使用SQLFIDDLE来实现这一点，我收到的错误是：

Schema Creation Failed: ERROR: syntax error at or near "+":

该功能如下所示，

CREATE OR REPLACE FUNCTION updateSalary() RETURNS VOID AS
$BODY$
DECLARE
  DECLARE sum INT DEFAULT 0;
  emp CURSOR FOR SELECT Dno, Salary FROM Employee;
  emp_row RECORD;
  dep CURSOR FOR SELECT Dno FROM Department;
  dep_row RECORD;
BEGIN
  open dep;
  LOOP
    FETCH dep into dep_row;
      exit when dep_row = null;
    open emp;
    LOOP
      FETCH emp into emp_row;
        exit when emp_row = null;
      if emp_row.Dno =dep_row.Dno then
        SET sum = sum + emp_row.salary;
      end if;

    END LOOP;
    UPDATE department SET total_sal = sum WHERE department.dno = emp_row.dno;
    close emp;
    SET sum = 0;
  END LOOP;
  close dep;
END;
$BODY$
  LANGUAGE plpgsql;

我相信这里有很多其他错误，所以如果有任何跳出来请告诉我，让我免受调试postgresql的美妙乐趣。

这是小提琴http://sqlfiddle.com/#!15/a1a45/3

由于某种原因，该功能未保存到该小提琴中。我认为为了让小提琴保存它必须能够建立起来。

Answer 1

下面提到几点

不需要游标......您只需在表employee和department之间进行联接。

以下是您应该尝试的内容

CREATE OR REPLACE FUNCTION updateSalary() RETURNS VOID 
AS
$BODY$
  DECLARE sum INT DEFAULT 0;

select sum = sum(emp.salary) 
FROM Employee emp
join Department dept
on emp.Dno = dept.Dno;

    UPDATE department as d SET total_sal = sum 
    FROM employee as e    
    WHERE d.dno = e.dno;
$BODY$
  LANGUAGE plpgsql;

修改

稍微修改了光标定义..试一试

CREATE OR REPLACE FUNCTION updateSalary() RETURNS VOID AS $BODY$ DECLARE sum INTEGER := 0; dep CURSOR FOR SELECT Dno FROM Department; dep_row Department%ROWTYPE; emp CURSOR(dept_Dno INTEGER) FOR <-- change here SELECT Dno, Salary FROM Employee WHERE Dno = dept_Dno; emp_row Employee%ROWTYPE; BEGIN open dep; LOOP FETCH dep into dep_row; exit when NOT FOUND; open emp( dep_row.Dno ); LOOP FETCH emp into emp_row; exit when NOT FOUND; sum := sum + emp_row.salary; END LOOP; UPDATE department SET total_sal = sum WHERE department.dno = emp_row.dno; close emp; sum := 0; END LOOP; close dep; END; $BODY$ LANGUAGE plpgsql;

您收到该错误导致未提及data type。我使用的是Parameterized Cursors。

Postgres中的函数和游标

1 个答案: