[newblue@[EMAIL PROTECTED]
~]$ cat Robert Klemme
> How come a db.geek doesn't know?
-_-
I'm a db beginner, I hope be come a db geek.
> Basically you have two options:
>
> 1. insert, catch error and update
>
> 2. update, check update row count and insert if 0
Now, I'm do it with this way. I post this topic, it is want to look for
a way better than this way, do it fast.
> Which of the two you choose depends on the RDBMS used as well as your
> expected distribution of data. IOW if you expect that most data sets
> will lead to an insert do approach 1 otherwise do 2.
>
> Also, there can be subtle issues with concurrent updates in scenario
> 2, i.e. the update can return 0 rows and the insert can still fail.
>
> Btw, why the strange naming of columns?
>
> Cheers
>
> robert
--
机器重新开动，系统重新安装，建立新的思想，迎接新的局面，一切重新再来
汝不可因难而妄自薄菲
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