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

you should add data from REFERENCES KEY in PRIMARY TABLE to FOREIGN KEY in CHILD TABLE
it means do not add random data to foreign key ، just use data from primary key that is accessable

description of data in foreign key