【ORACLE】大数据快速更新（游标分批提交)

--【避免回滚段过大】
--删除索引，最后恢复索引
--分批插入
DECLARE
CURSOR c1 IS 
        SELECT ROWID row_id 
          FROM ts_batchcode WHERE dr=0 
          order by rowid;
c_commit CONSTANT PLS_INTEGER := 10000;
--CONSTANT 变量
--PLS_INTEGER可以存储一个有符号的整形值
BEGIN
  FOR c1rec IN c1 LOOP
        insert into tmp111 select * from ts_batchcode a
          WHERE a.ROWID = c1rec.row_id;
        IF (MOD(c1%ROWCOUNT,c_commit) = 0)
        THEN
          COMMIT;
        END IF;
  END LOOP;
  COMMIT;
END;
/


--分批update
DECLARE
CURSOR c1 IS 
        SELECT ROWID row_id 
          FROM CPCOLLECTION --更新目标表
          order by rowid;
c_commit CONSTANT PLS_INTEGER := 10000;
--CONSTANT 变量
--PLS_INTEGER可以存储一个有符号的整形值
BEGIN
  FOR c1rec IN c1 LOOP
        update CPCOLLECTION a set ...... 
        where ......
          and a.rowid=c1rec.row_id;
        IF (MOD(c1%ROWCOUNT,c_commit) = 0)
        THEN
          COMMIT;
        END IF;
  END LOOP;
  COMMIT;
END;
/



--分批删除gl_detail垃圾数据
DECLARE
CURSOR c1 IS 
        SELECT /*+ parallel(gl_detail) */ ROWID row_id 
          FROM gl_detail 
          WHERE dr=1 order by rowid;
c_commit CONSTANT PLS_INTEGER := 10000;
BEGIN
  FOR c1rec IN c1 LOOP
        DELETE FROM gl_detail
          WHERE ROWID = c1rec.row_id;
        IF (MOD(c1%ROWCOUNT,c_commit) = 0)
        THEN
          COMMIT;
        END IF;
  END LOOP;
  COMMIT;
END;
/