将一个 table 复制到另一个加上依赖于另一列的一列

Question

NAME 和 VER 是主键。我不会写下我想做的事情，而是会画画。

Table 来源：

NAME | SOMETHING1 | VER | SOMETHING2 | MODDATIME
john | bob        | 1   | doe        | 18-AUG-14 10.16.08.695221100 AM
john | bob        | 2   | doe        | 19-AUG-14 11.01.42.109826000 AM
john | bob        | 3   | doe        | 09-SEP-14 10.14.15.929342100 AM
john | bob        | 4   | doe        | 10-SEP-14 10.14.15.929342100 AM

Table 目标：

NAME | SOMETHING1 | VER | SOMETHING2 | MODDATIME                       | DATEUP
john | bob        | 1   | doe        | 18-AUG-14 10.16.08.695221100 AM | 19-AUG-14 11.01.42.109826000 AM
john | bob        | 2   | doe        | 19-AUG-14 11.01.42.109826000 AM | 09-SEP-14 10.14.15.929342100 AM
john | bob        | 3   | doe        | 09-SEP-14 10.14.15.929342100 AM | 10-SEP-14 10.14.15.929342100 AM
john | bob        | 4   | doe        | 10-SEP-14 10.14.15.929342100 AM | 31-DEC-99 0.0.0.0 AM

谢谢。

Answer 1

用相同的Table做一个OUTER JOIN得到结果

SELECT a.NAME,
       a.something,
       a.VER,
       a.something,
       a.MODDATIME,
       Ifnull(b.MODDATIME,'31-DEC-99 0.0.0.0 AM') AS DateUP
FROM   Yourtable a
       LEFT OUTER JOIN Yourtable b
              ON a.NAME = b.NAME
                 AND a.VER = b.VER - 1

将一个 table 复制到另一个加上依赖于另一列的一列

Copying one table to another plus one column dependant of another column

mysql

sql

insert-into