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

Question

I have created tables in MySQL Workbench as shown below :

ORDRE table:

CREATE TABLE Ordre (
  OrdreID   INT NOT NULL,
  OrdreDato DA         


        

Answer 1

In my case the tables were perfectly consistent.

Anyway I was getting this error because I created (by accident) more than one FK constraint on the same field.

I run the following query to show all the keys:

SELECT *
FROM information_schema.table_constraints
WHERE constraint_schema = 'my_db_name'

and I deleted the wrong ones with the following query:

ALTER TABLE my_table
DROP FOREIGN KEY wrong_fk_constraint; 

You can check it also running this query:

SHOW CREATE TABLE my_table;