Question

我坚持如何从前一个插入语句中获得递增的id和max，min，sum或count。

任何人都可以建议我如何以简单的方式做到这一点吗？

CREATE PROCEDURE INSERTRECORD()
BEGIN
INSERT INTO tb_normalized_data_20110615
SELECT * FROM tb_normalized_data WHERE 
       date_added BETWEEN '2011-06-15 01:10:00' and '2011-06-15 01:19:59'

-- Stuck here how to get the value for(x_min_id, x_max_id, x_min_date,
--  x_max_date) from the statement above without querying again?

INSERT INTO tb_backup_tracker(min_id, max_id, min_date, max_date)
VALUES(x_min_id, x_max_id, x_min_date, x_max_date);

END;

Answer 1

我认为你正在寻找一个cursor。基本上，这是它的工作方式：

DECLARE cur CURSOR FOR SELECT * FROM tb_normalized_data WHERE 
       date_added BETWEEN '2011-06-15 01:10:00' and '2011-06-15 01:19:59';
DECLARE ID INT;
DECLARE DT DATE;/* Declare all of your columns */
DECLARE MIN_ID INT;
DECLARE MAX_ID INT;
DECLARE MIN_DATE DATE;
DECLARE MAX_DATE DATE;
-- add your other columns here...
BEGIN
  OPEN cur;

  read_loop: LOOP
    FETCH cur INTO ID, DT /* Fetch into all of your columns */;
    IF ID < MIN_ID THEN
       SET @MIN_ID = ID;
    IF ID > MAX_ID THEN
       SET @MAX_ID = ID;
    END IF;
    INSERT INTO tb_normalized_data_20110615 (ID, DATE_ADDED 
           /*, rest of your columns*/ ) VALUES( /* columns */ );
  END LOOP;
  INSERT INTO tb_backup_tracker(min_id, max_id, min_date, max_date)
      VALUES(min_id, max_id, min_date, max_date);
  CLOSE cur;

Answer 2

使用光标循环遍历数据并在光标循环内部插入和以跟踪最小/最大值，无论您需要什么。

此外，您的代码很脆弱：避免使用模式INSERT INTO TABLE SELECT * FROM ...;如果第二个表添加了一个SQL，那么SQL将会中断。最好明确命名列。

如果您需要光标帮助，请发布。

Mysql存储过程在插入后获取总计数

2 个答案: