Question

我正在将一个Oracle函数移植到Postgres PGPLSQL中..我一直在使用本指南：http://www.postgresql.org/docs/8.1/static/plpgsql.html

CREATE OR REPLACE PROCEDURE DATA_UPDATE
  (mission  NUMBER,
   task     NUMBER)
AS
BEGIN
IF mission IS NOT NULL THEN
  UPDATE MISSION_OBJECTIVE MO
     SET (MO.MO_TKR_TOTAL_OFF_SCHEDULED,
          MO.MO_TKR_TOTAL_RECEIVERS) =
           (SELECT NVL(SUM(RR.TRQ_FUEL_OFFLOAD),0),
                   NVL(SUM(RR.TRQ_NUMBER_RECEIVERS),0)
              FROM REFUELING_REQUEST RR, MISSION_REQUEST_PAIRING MRP
             WHERE MO.MSN_INT_ID = MRP.MSN_INT_ID
               AND MO.MO_INT_ID = MRP.MO_INT_ID
               AND MRP.REQ_INT_ID = RR.REQ_INT_ID)
   WHERE MO.MSN_INT_ID = mission
     AND MO.MO_INT_ID = task ;
END IF ;
COMMIT ;
END ;

我到目前为止：

CREATE OR REPLACE FUNCTION DATA_UPDATE
  (NUMERIC,
   NUMERIC)
   RETURNS integer as '
   DECLARE
   mission ALIAS for $1;
   task ALIAS for $2;
BEGIN
IF mission IS NOT NULL THEN
  UPDATE MISSION_OBJECTIVE MO
     SET (MO.MO_TKR_TOTAL_OFF_SCHEDULED,
          MO.MO_TKR_TOTAL_RECEIVERS) =
           (SELECT COALESCE(SUM(RR.TRQ_FUEL_OFFLOAD),0),
                   COALESCE(SUM(RR.TRQ_NUMBER_RECEIVERS),0)
              FROM REFUELING_REQUEST RR, MISSION_REQUEST_PAIRING MRP
             WHERE MO.MSN_INT_ID = MRP.MSN_INT_ID
               AND MO.MO_INT_ID = MRP.MO_INT_ID
               AND MRP.REQ_INT_ID = RR.REQ_INT_ID)
   WHERE MO.MSN_INT_ID = mission
     AND MO.MO_INT_ID = task ;
END IF;
COMMIT;
END;
' LANGUAGE plpgsql;

这是我得到的错误：

ERROR:  syntax error at or near "SELECT"
LINE 1: ...OTAL_OFF_SCHEDULED, MO.MO_TKR_TOTAL_RECEIVERS) = (SELECT COA...

我不知道为什么这不起作用......有什么想法吗？

Answer 1

我认为Postgres不支持更新构造（我尝试的简单测试失败并出现相同的错误）。你可能需要这样做：

CREATE OR REPLACE FUNCTION DATA_UPDATE
  (mission NUMERIC,
   task NUMERIC)
   RETURNS void as '
DECLARE
   offScheduled int4;
   totalReceivers int4; 
BEGIN
IF mission IS NOT NULL THEN
  select COALESCE(SUM(RR.TRQ_FUEL_OFFLOAD),0),
  COALESCE(SUM(RR.TRQ_NUMBER_RECEIVERS),0) into offScheduled, totalReceivers 
  FROM REFUELING_REQUEST RR, MISSION_REQUEST_PAIRING MRP
             WHERE MO.MSN_INT_ID = MRP.MSN_INT_ID
               AND MO.MO_INT_ID = MRP.MO_INT_ID
               AND MRP.REQ_INT_ID = RR.REQ_INT_ID;

 UPDATE MISSION_OBJECTIVE MO
     SET MO.MO_TKR_TOTAL_OFF_SCHEDULED = offScheduled,
          MO.MO_TKR_TOTAL_RECEIVERS = totalReceivers 
     WHERE MO.MSN_INT_ID = mission
     AND MO.MO_INT_ID = task ;
END IF;
END;
' LANGUAGE plpgsql;

...假设我没有严重破坏逻辑;）

我冒昧地改变了参数的定义方式和返回类型（因为看起来你实际上并没有从函数中返回任何东西？）

编辑：oops，我使用了select into的错误构造...

Answer 2

PostgreSQL在其UPDATE语法中支持FROM扩展。 Find out more

所以这样的事情对你有用......

  UPDATE MISSION_OBJECTIVE MO
     SET MO.MO_TKR_TOTAL_OFF_SCHEDULED = COALESCE(SUM(RR.TRQ_FUEL_OFFLOAD),0),
          MO.MO_TKR_TOTAL_RECEIVERS) = COALESCE(SUM(RR.TRQ_NUMBER_RECEIVERS),0)
              FROM REFUELING_REQUEST RR, MISSION_REQUEST_PAIRING MRP
             WHERE MRP.MSN_INT_ID = mission
               AND  MRP.MO_INT_ID = task
               AND MRP.REQ_INT_ID = RR.REQ_INT_ID
   AND MO.MSN_INT_ID = MRP.MSN_INT_ID 
     AND MO.MO_INT_ID = MRP.MO_INT_ID

将Oracle过程移植到PostgreSQL

2 个答案: