Re: SELECT through many databases

[Brent Baisley]

On Fri, Nov 21, 2008 at 12:44 PM, Andre Matos <[EMAIL PROTECTED]> wrote:
> Hello,
>
> Let's suppose I have 5 database: db1, db2, db3, db4, and db5. They all have
> the same structure but different data.
>
> I would like perform this select
>
> SELECT TaskDoneOn, TaskDoneBy
> FROM {database}
> WHERE TaskDoneOn IS NOT NULL
>
> and collect the data from all 5 database. However, I would like to avoid
> doing something like this:
>
> SELECT TaskDoneOn, TaskDoneBy
> FROM db1
> WHERE TaskDoneOn IS NOT NULL
> UNION
> SELECT TaskDoneOn, TaskDoneBy
> FROM db2
> WHERE TaskDoneOn IS NOT NULL
> UNION
> SELECT TaskDoneOn, TaskDoneBy
> FROM db3
> WHERE TaskDoneOn IS NOT NULL
> UNION
> SELECT TaskDoneOn, TaskDoneBy
> FROM db4
> WHERE TaskDoneOn IS NOT NULL
> UNION
> SELECT TaskDoneOn, TaskDoneBy
> FROM db5
> WHERE TaskDoneOn IS NOT NULL
>
>
> Today I have 5, but tomorrow I can have 50 and I don't want to forget any
> database.
>
> Thanks for any help.
>
> Andre

Create a MERGE table that is all those tables combined. Then you just
need to do 1 select as if it was one table. Just be sure to update the
MERGE table description when ever you add a table.

Brent Baisley

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