Skip to main content

Constraints

Primary Key​

Single Column​

int64 id = 1 [(ratel.column) = {
  constraints: { primary_key: true }
}];

Composite​

option (ratel.table) = {
  generate: true
  primary_key: { columns: ["order_id", "line_no"] }
};

Unique​

Single Column​

string email = 2 [(ratel.column) = {
  constraints: { unique: true }
}];

Composite​

option (ratel.table) = {
  generate: true
  unique: [
    { columns: ["order_id", "product_id"] }
  ]
};

Default Values​

google.protobuf.Timestamp created_at = 4 [(ratel.column) = {
  constraints: { default_value: "now()" }
}];

bool is_active = 5 [(ratel.column) = {
  constraints: { default_value: "true" }
}];

CHECK Constraints​

Column-Level​

string code = 1 [(ratel.column) = {
  constraints: { check: "code <> ''" }
}];

Table-Level​

option (ratel.table) = {
  generate: true
  constraints: [
    "CHECK (status IN ('NEW', 'PAID', 'CANCELLED'))"
  ]
};

Foreign Key References​

Reference another table's column:

int64 user_id = 2 [(ratel.column) = {
  constraints: {
    references_table: "users"
    references_column: "id"
    on_delete: CASCADE
  }
}];

Cross-Schema References​

Use references_schema for tables in a different schema:

int64 user_id = 2 [(ratel.column) = {
  constraints: {
    references_schema: "auth"
    references_table: "users"
    references_column: "id"
    on_delete: CASCADE
  }
}];

Generates: REFERENCES "auth"."users"(id) ON DELETE CASCADE

Reference Actions​

Available actions for on_delete and on_update:

ActionDescription
NO_ACTIONDefault — raise error if referenced row exists
CASCADEDelete/update dependent rows
SET_NULLSet FK column to NULL
SET_DEFAULTSet FK column to its default value
RESTRICTLike NO_ACTION but not deferrable
int64 order_id = 1 [(ratel.column) = {
  constraints: {
    references_schema: "store"
    references_table: "orders"
    references_column: "id"
    on_delete: CASCADE
    on_update: NO_ACTION
  }
}];

Raw Constraints​

For anything not covered by structured options:

string code = 1 [(ratel.column) = {
  constraints: {
    raw: "COLLATE \"C\" NOT NULL"
  }
}];

Go Approach​

col := schema.BigIntColumn(UsersColID,
    ddl.WithPrimaryKey[UsersColumnAlias](),
    ddl.WithNotNull[UsersColumnAlias](),
)

fkCol := schema.BigIntColumn(OrdersColUserID,
    ddl.WithNotNull[UsersColumnAlias](),
    ddl.WithReferences[UsersColumnAlias]("users", "id"),
    ddl.WithOnDelete[UsersColumnAlias]("CASCADE"),
)