query in multiple DB

[PHPycho]

Suppose i have three dbs on the same server.
DB #1:

host: localhost
user: root1
pass: pass1
Db: db1

DB #2:

host: localhost
user: root2
pass: pass2
Db: db2

DB #3:

host: localhost
user: root3
pass: pass3
Db: db3

You have noticed from above that i have three DBs on the same server but have different users.

Summary of DBs
DB #1 is use for main login page.
DB #2 has table called products2

[CODE]products2

id
sku
name
...
[/CODE]
DB #3 has table called products3

[CODE]products3

id
sku
name
....
[/CODE]
What i want to do is:
I want perform query in DB #2's products2 table & DB #3's products3 so that i can display the products with common sku.
Hope my problem is clear.

My Question is:
1> is it possible to make a single query for two database? If yes how?
2> if above is not possible then,
Would it be effective to make separate fetching from two dbs as an arrays.
And manipulating that array for the required results?

Thanks

[halojoy]

Question 1.
I dont think so.
But it is possible to open 2 handles to 2 different DB in same script.

Question 2.
I think a better solution would be to move those tables
that need to interact into one and the same database.
This is the usual approach. Will cause less headache!

[PHPycho]

@, we cannot move that tables to one db as that is the requirement of the client.
Can't we perform like:
SELECT fields FROM db2.products2 INNER JOIN db3.products3 ON products2.sku = products3.sku

[johanafm]

Yes you can. All that matters are the accessrights of the users. As such, root3 will need to be granted (at least) SELECT on db2.* (or subset thereof). Or if it's root2 that needs the same for db3... Or both.