mysql - Error in foreignkey table -

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i created database structure using mysql workbench. when forward engineer or synchronize model displays errors. when remove foreign key or if connect "int" foreign key second table it's working fine. want use "varchar(255)". can't use "varchar(255)" foreign key? if please me fix error. can't forward engineer table.enter image description here

yes can use varchar foreign key.it appropriate add unique index or unique constraint table. however, primary key should "meaningless" value, such auto-incremented number or guid.


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