Gorm How to add unique constraint on combined multiple columns in gorm.

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How to add unique constraint on combined multiple columns in gorm. Structure Look like this type DumyProject struct { DumyProjectId int gorm:"type:integer primary key GENERATED ALWAYS AS IDENTITY ( INCREMENT 1 START 1 MINVALUE 1 MAXVALUE 2147483647 CACHE 1 );not null;" ProjectId int gorm:"type:integer;not null;" PracticeAreaName string gorm:"type:varchar;not null;"

}

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I want to add constraint like: CONSTRAINT dummy_project_values_un UNIQUE (dummy_project_id, dummy_field_id)

type DumyProject struct.docx.tar.gz

Comment From: ashupednekar

Use the same unique index on the fields you need to be unique together, like so..

type GroupUserMap struct {
    ID      int `gorm:"primaryKey"`
    GroupID int
    Group   Groups `uniqueIndex:idx_user_grp_uniq_together"`
    UserID  int
    User    Users `uniqueIndex:idx_user_grp_uniq_together"`
}

This will result in indexes like so...

console=# \d group_user_maps;
                             Table "public.group_user_maps"
  Column  |  Type  | Collation | Nullable |                   Default
----------+--------+-----------+----------+---------------------------------------------
 id       | bigint |           | not null | nextval('group_user_maps_id_seq'::regclass)
 group_id | bigint |           |          |
 user_id  | bigint |           |          |
Indexes:
    "group_user_maps_pkey" PRIMARY KEY, btree (id)
    "idx_user_grp_uniq_together" UNIQUE, btree (group_id, user_id)
Foreign-key constraints:
    "fk_group_user_maps_group" FOREIGN KEY (group_id) REFERENCES groups(id)
    "fk_group_user_maps_user" FOREIGN KEY (user_id) REFERENCES users(id)

Hope it helps :)

Comment From: Abhishek-Mali-Personal

@ashupednekar This would create a unique index what i really want is to create a unique constraint not a unique index