Mysql使用上一条记录中的值更新记录

Question

我有下表,我要做的是更新,例如,RefIDs 3-14具有相同的状态值"已添加"作为前一个值.我想这样做,直到达到下一个完成的值.因此,当遇到"已添加"时,它会更新下面所有具有"已添加"空值的行,直到它到达具有已填充状态的下一个RefID,然后更新下一批值.可以这样做吗？任何帮助将不胜感激.我正在寻找这个动态,因为我不想手动更新,例如,Status ="Added",其中RefID是3.

RefID Status


1 Null

2 Added

3 Null

4 Null

5 Changed

6 Null

7 Null

RefID Status

1 Null


2 Added


3 Added


4 Added


5 Changed


6 Changed


7 Changed

RefID Status

1 Null

2 Added

3 Null

4 Null

5 Changed

6 Null

7 Null

我想要实现的是:

RefID Status


1 Null

2 Added

3 Added

4 Added

5 Changed

6 Changed

7 Changed

RefID Status

1 Null


2 Added


3 Null


4 Null


5 Changed


6 Null


7 Null

RefID Status

1 Null

2 Added

3 Added

4 Added

5 Changed

6 Changed

7 Changed

Answer 1

试试这个查询 -

UPDATE refs_table t1
  JOIN (
    SELECT RefID, @s:=IF(Status IS NULL, @s, Status) Status
      FROM (SELECT * FROM refs_table ORDER BY RefID) r,
    (SELECT @s:=NULL) t
  ) t2
  ON t1.RefID = t2.RefID
SET t1.Status = t2.Status