The situation is as follows:
DB server: MySQL 5…..
phpMyAdmin version 3.3.10
There is a “master” database. Let its name be mainDb, there are (in theory) infinitely many databases db_1, db_2, etc.
All tables of type InnoDB.
In the config file, lines like $cnf…..[‘pma’], $cnf…..[‘pmadb’], $cnf…..[‘pma_relation’] are commented out.
Task: set a foreign key via the phpMyAdmin web interface, for example, for the db_1.component.type_id field to the mainDb.type.type_id field.
Now “Structure”->”Links” it is possible to set links to the fields of the tables of the current database. Where to look? Where to click? Poke your nose, please. You need to learn how to set keys on the fields of tables of any database.
Question removed. As it turns out, this is impossible. Only write foreign keys to the fields of tables of external databases with handles