When I m trying to create a foreign key linked to a primary key in another table I get:
#1452 - Cannot add or update a child row: a foreign key constraint fails
(`fayer`.`#sql-225c_1d3`, CONSTRAINT `#sql-225c_1d3_ibfk_1` FOREIGN KEY (`country_id`)
REFERENCES `countries` (`id`) ON DELETE CASCADE)
I have checked that all tables are using innodb and the datatype are both "int".
What is the problem?
You have rows that violate the constraint you re trying to add.
In this particular case, there are values in your country_id column that do not exist in id column of countries table.
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