Error Number: 1452 problem

[dimis283]

I have a table at mysql that has a foreign key at another table (product_code and product).
Until yesterday all where ok but today when I try to insert values at product_code there is the error

Error Number: 1452
Cannot add or update a child row: a foreign key constraint fails

is here.
We do nothing at db, at toad once I have the cursor up this table, the free innodb:9216 kb message is here.
What is wrong?
Dimis

[dimis283]

I found it, after a mysql problem we recreate the tables and product was myisam and not innodb.
Dimis

[r937]

the row you are attempting to update or insert contains a value in a foreign key which does not exist in the key column of the table it references

[tripy]

It's because that the value in the field with a foreign key constraint that you insert have no reference into the parent table.

It's what foreign key are doing, enforcing you to insert a value that exists.
http://dictionary.die.net/foreign%20key