Is this work for mysql foreign keys?

Question

In the past few years, I have read many articles on foreign keys in MySQL, but nothing recent. I know that they are good for use on something like a forum topic that has a child post, if I delete a topic with a message 100 related to this topic, foreign keys will make it delete those 100 topics for me, I’m still right then?

I am working on a social network in php / mysql, there is a user table with a user ID, then there are about 10 other tables that are associated with this table with this user ID field, should I use foreign keys on this? I will not need to update all tables, but, for example, if a user deletes this account, in the past I would run PHP as 10 delete requests, 1 for each table for the user. Is it good to use foreign keys?

Answer 1

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Answer 2

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Answer 3

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Answer 4

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Answer 5

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http://dev.mysql.com/doc/refman/5.1/en/innodb-foreign-key-constraints.html

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