mysql relationships

[Anon]

I have one database with several tables. I want to of the tables to have a relational field. Hod do I establish the relationship? Is it done by sharing a common field name?

[spider_man]

I think this is not a forum question but an in-depth reading of relational algebra.

[Anon]

Yep, usually you just link by using common primary keys (like IDs).

[toma42]

er, Pablo, bad answer.

MySQL doesn't support referential integrity (so no amount of reading will tell him how, P), so to create a foreign key most people use a naming scheme and put an index on the column.

Personally, I use
t1
t1_key

t2
t2_key
ref_t1

so I know a foreign key is a fkey by the ref_ and I know the table it references too.

[spider_man]

So, what is it that you are applying to solve the problem?

[toma42]

The solution I gave above is the correct one for mysql.

[Anon]

http://www.mysql.com/doc/e/x/example-Foreign_keys.html

This is a good resource too.

[spider_man]

Yeap. And that's relational algebra, wether the database supports referential constraints or not.

[Anon]

i print out the schema and highlight the relationships with different colors to represent each table 🙂 mysql adds a little bit of color to my cube.