MySQL Error 1215: Cannot add foreign key constraint

Question

I am trying to forward engineer my new schema onto my db server, but I can\'t figure out why I am getting this error. I\'ve tried to search for the answer here, but everyth

Answer 1

For MySQL (INNODB) ... get definitions for columns you want to link

SELECT * FROM information_schema.columns WHERE 
TABLE_NAME IN (tb_name','referenced_table_name') AND 
COLUMN_NAME  IN ('col_name','referenced_col_name')\G

compare and verify both column definitions have

same COLUMN_TYPE(length), same COLATION

could be helpfull to play like

set foreign_key_checks=0;
ALTER TABLE tb_name ADD FOREIGN KEY(col_name) REFERENCES ref_table(ref_column) ON DELETE ...
set foreign_key_checks=1;