MySQL Workbench rename constraint -

i use mysql workbench design database , export sql create script. when run script create database, error - errno: 121.

it turns out mysql workbench gives 2 constraints same name, because both constraints use same key (i have table primary key 'roleid' , reference key in 2 other tables).

is there way how can rename constraint directly in designer, when forward engineer sql create script, give no errors?

i tried double click relation in designer , give new caption, still generates script original name.

part of generated script creates error:

 create  table if not exists users.roles (   roleid int not null auto_increment ,   ...   primary key (roleid) ,   ...);
  
create  table if not exists users.userroles (   ...   roleid int not null ,   ...   constraint roleid     foreign key (roleid )     references users.roles (roleid ));
  
create  table if not exists users.resourceprivileges (   roleid int not null ,   ...   constraint roleid     foreign key (roleid )     references users.roles (roleid )); 

not sure how ended that. took mysql workbench spin, created 2 tables fk , created

-- ----------------------------------------------------- -- table `mydb`.`users` -- ----------------------------------------------------- create  table if not exists `mydb`.`users` (   `idusers` int null ,   primary key (`idusers`) ) engine = innodb;   -- ----------------------------------------------------- -- table `mydb`.`usersroles` -- ----------------------------------------------------- create  table if not exists `mydb`.`usersroles` (   `users_idusers` int not null ,   primary key (`users_idusers`) ,   constraint `fk_usersroles_users`     foreign key (`users_idusers` )     references `mydb`.`users` (`idusers` )     on delete no action     on update no action) engine = innodb; 

notice constraint has unique name 'fk_usersroles_users' not duplicated since uses table names. fun added relationship between same tables , default get

-- ----------------------------------------------------- -- table `mydb`.`usersroles` -- ----------------------------------------------------- create  table if not exists `mydb`.`usersroles` (   `users_idusers` int not null ,   `users_idusers1` int not null ,   primary key (`users_idusers`, `users_idusers1`) ,   index `fk_usersroles_users1` (`users_idusers1` asc) ,   constraint `fk_usersroles_users`     foreign key (`users_idusers` )     references `mydb`.`users` (`idusers` )     on delete no action     on update no action,   constraint `fk_usersroles_users1`     foreign key (`users_idusers1` )     references `mydb`.`users` (`idusers` )     on delete no action     on update no action) engine = innodb; 

which again non problem (all of above auto generated - have set table names, primary key on referenced table , added 2 1:n relationships)

notes: version 5.2.30.

edit maybe happened preferences. default name fk constraints defined on model tab.