批量更新速度

1.使用临时表比较快
/*更新受理者名称*/
UPDATE
(SELECT SC.RECEIPT_NAME,C.CONNECTION_NAMEC FROM KAMS_SERVICE_CALL SC
INNER JOIN  CONNECTION_M C
ON SC.RECEIPT_RESOURCE_TYPE = C.RESOURCE_TYPE
AND SC.RECEIPT_CONNECTION_CODE = C.CONNECTION_CODE
AND SC.RECEIPT_CONNECTION_TYPE = C.CONNECTION_TYPE
AND C.CONNECTION_NAMEC IS NOT NULL) SET
RECEIPT_NAME=CONNECTION_NAMEC
/
2.可以只连接一张表取到的列不要连接视图去取，速度更快

3.根据地址找市：
主表数据4万条
速度慢：102秒
begin
       for cu in (SELECT CITY_CODE,CITY_NAME FROM KAMS_M_CITY) loop
          begin
              for re in (SELECT
                              ADDR1,
                              RESOURCE_TYPE,
                              CONNECTION_CODE,
                              CONNECTION_TYPE
                          FROM CONNECTION_M
                          WHERE ADDR1 IS NOT NULL
                          AND ADDR1 like '%'||cu.CITY_NAME||'%')
              loop
                  begin
                     UPDATE  CONNECTION_M
                     SET KAMS_CITY_CODE = cu.CITY_CODE
                     WHERE RESOURCE_TYPE = re.RESOURCE_TYPE
                     AND CONNECTION_CODE = re.CONNECTION_CODE
                     AND CONNECTION_TYPE = re.CONNECTION_TYPE;
                  end;
               end loop;
           end;
       end loop;
end;

速度慢：84秒
begin
       for re in (
          SELECT
              RESOURCE_TYPE,
              CONNECTION_CODE,
              CONNECTION_TYPE,
              CITY_CODE
          FROM CONNECTION_M
          INNER JOIN KAMS_M_CITY
          ON ADDR1 IS NOT NULL
          AND ADDR1 like '%'||CITY_NAME||'%')
       loop
          begin
                     UPDATE  CONNECTION_M
                     SET KAMS_CITY_CODE = re.CITY_CODE
                     WHERE RESOURCE_TYPE = re.RESOURCE_TYPE
                     AND CONNECTION_CODE = re.CONNECTION_CODE
                     AND CONNECTION_TYPE = re.CONNECTION_TYPE;
           end;
       end loop;
end;

较快46秒
UPDATE CONNECTION_M a
SET KAMS_CITY_CODE =
(SELECT CITY_CODE
FROM CONNECTION_M m
INNER JOIN KAMS_M_CITY c
ON  m.ADDR1 IS NOT NULL
AND m.ADDR1 like c.CITY_NAME||'%'
WHERE a.RESOURCE_TYPE = m.RESOURCE_TYPE
AND a.CONNECTION_CODE = m.CONNECTION_CODE
AND a.CONNECTION_TYPE = m.CONNECTION_TYPE)
/