Description:
Provide a bit more details when FK constraints fail in NDB.
Today we (NDB API + MySQL) are not giving any hints in error message of which of multiple FK's that triggered the error.
See sample below on world database:
> mysql> insert into city values (9999,"KALLE1","XYZ","KALLE3",9898);
> ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (Unknown error code)
Can we add some hints in NdbError:"ERROR Details" (here: https://dev.mysql.com/doc/ndbapi/en/ndb-ndberror.html) regarding which FK that was violated and return this information to client.
For InnoDB SE we are providing this information in error message back to client:
> mysql> insert into city values (9999,"KALLE1","XYZ","KALLE3",9898);
> ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`world`.`city`, CONSTRAINT `city_ibfk_1` FOREIGN KEY (`CountryCode`) REFERENCES `country` (`Code`))
How to repeat:
Import world database into NDB:
create database world;
use world;
source /home/ted/ws/world.sql
alter table city drop foreign key city_ibfk_1;
alter table countrylanguage drop foreign key countryLanguage_ibfk_1;
alter table countrylanguage engine=ndbcluster;
alter table city engine=ndbcluster;
alter table country engine=ndbcluster;
ALTER TABLE city ADD CONSTRAINT `city_ibfk_1` FOREIGN KEY (`CountryCode`) REFERENCES `country` (`Code`);
ALTER TABLE countrylanguage ADD CONSTRAINT `countryLanguage_ibfk_1` FOREIGN KEY (`CountryCode`) REFERENCES `coun
try` (`Code`);
Run query below:
> mysql> insert into city values (9999,"KALLE1","XYZ","KALLE3",9898);
> ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (Unknown error code)
For InnoDB SE you will get this information in error message:
> mysql> insert into city values (9999,"KALLE1","XYZ","KALLE3",9898);
> ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`world`.`city`, CONSTRAINT `city_ibfk_1` FOREIGN KEY (`CountryCode`) REFERENCES `country` (`Code`))
