assorted: foreign keys, mult databases, and crashes

[Tofu Optimist]

Hi ----

Three questions from a Mysql newcomer....

Syntax question:

Can a table in database A have a foreign key
relationship with a table in database B? (both INNODB,
both with appropriate indexes, etc)

Architecture question:

What is the rule-of-thumb to use use multiple
databases, rather than one huge database with many
tables?  Is splitting one database into multiple
databases just a way to organize data (eg I use
folders and subfolders on my file system, not
everything is at root) or are there performance /
security / reliablity / backup / other issues?

System question:

Mysql doesn't use transaction logs, does it?
How does one restore a mysql database if it crashes in
the middle of a large operation?

Thanks


TO

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