>> I think you're confusing referential constraints with foreign keys.
> In my book, referential constraints and foreign key constraints (the full
> are the same.
Yes, referential constraints and foreign key constraints are the same thing.
Notice the word constraints.
Let me say this again:
A foreign key is merely a column which references a primary key or a unique
key in the same or another table.
A referential constraint (or foreign key constraint if you prefer) defines
an integrity condition that must be satisfied by all the rows in two tables.
See the difference? So yes, MyISAM has foreign keys, no MyISAM does not
have foreign key constraints. Kindly don't go around saying MyISAM doesn't
have foreign keys because it simply makes no sense. Referential integrety
is not required for foreign keys. The only thing you need to have a foreign
key is a column which contains the value of a primary key or unique key in