doc/edges: add erds to examples (#3268)

examples/o2mrecur/ent/migrate/schema.go

@@ -16,7 +16,7 @@ var (
 	NodesColumns = []*schema.Column{
 		{Name: "id", Type: field.TypeInt, Increment: true},
 		{Name: "value", Type: field.TypeInt},
-		{Name: "node_children", Type: field.TypeInt, Nullable: true},
+		{Name: "parent_id", Type: field.TypeInt, Nullable: true},
 	}
 	// NodesTable holds the schema information for the "nodes" table.
 	NodesTable = &schema.Table{

examples/o2mrecur/ent/mutation.go

@@ -204,9 +204,53 @@ func (m *NodeMutation) ResetValue() {
 	m.addvalue = nil
 }
 
-// SetParentID sets the "parent" edge to the Node entity by id.
-func (m *NodeMutation) SetParentID(id int) {
-	m.parent = &id
+// SetParentID sets the "parent_id" field.
+func (m *NodeMutation) SetParentID(i int) {
+	m.parent = &i
+}
+
+// ParentID returns the value of the "parent_id" field in the mutation.
+func (m *NodeMutation) ParentID() (r int, exists bool) {
+	v := m.parent
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldParentID returns the old "parent_id" field's value of the Node entity.
+// If the Node object wasn't provided to the builder, the object is fetched from the database.
+// An error is returned if the mutation operation is not UpdateOne, or the database query fails.
+func (m *NodeMutation) OldParentID(ctx context.Context) (v int, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldParentID is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldParentID requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldParentID: %w", err)
+	}
+	return oldValue.ParentID, nil
+}
+
+// ClearParentID clears the value of the "parent_id" field.
+func (m *NodeMutation) ClearParentID() {
+	m.parent = nil
+	m.clearedFields[node.FieldParentID] = struct{}{}
+}
+
+// ParentIDCleared returns if the "parent_id" field was cleared in this mutation.
+func (m *NodeMutation) ParentIDCleared() bool {
+	_, ok := m.clearedFields[node.FieldParentID]
+	return ok
+}
+
+// ResetParentID resets all changes to the "parent_id" field.
+func (m *NodeMutation) ResetParentID() {
+	m.parent = nil
+	delete(m.clearedFields, node.FieldParentID)
 }
 
 // ClearParent clears the "parent" edge to the Node entity.
@@ -216,15 +260,7 @@ func (m *NodeMutation) ClearParent() {
 
 // ParentCleared reports if the "parent" edge to the Node entity was cleared.
 func (m *NodeMutation) ParentCleared() bool {
-	return m.clearedparent
-}
-
-// ParentID returns the "parent" edge ID in the mutation.
-func (m *NodeMutation) ParentID() (id int, exists bool) {
-	if m.parent != nil {
-		return *m.parent, true
-	}
-	return
+	return m.ParentIDCleared() || m.clearedparent
 }
 
 // ParentIDs returns the "parent" edge IDs in the mutation.
@@ -331,10 +367,13 @@ func (m *NodeMutation) Type() string {
 // order to get all numeric fields that were incremented/decremented, call
 // AddedFields().
 func (m *NodeMutation) Fields() []string {
-	fields := make([]string, 0, 1)
+	fields := make([]string, 0, 2)
 	if m.value != nil {
 		fields = append(fields, node.FieldValue)
 	}
+	if m.parent != nil {
+		fields = append(fields, node.FieldParentID)
+	}
 	return fields
 }
 
@@ -345,6 +384,8 @@ func (m *NodeMutation) Field(name string) (ent.Value, bool) {
 	switch name {
 	case node.FieldValue:
 		return m.Value()
+	case node.FieldParentID:
+		return m.ParentID()
 	}
 	return nil, false
 }
@@ -356,6 +397,8 @@ func (m *NodeMutation) OldField(ctx context.Context, name string) (ent.Value, er
 	switch name {
 	case node.FieldValue:
 		return m.OldValue(ctx)
+	case node.FieldParentID:
+		return m.OldParentID(ctx)
 	}
 	return nil, fmt.Errorf("unknown Node field %s", name)
 }
@@ -372,6 +415,13 @@ func (m *NodeMutation) SetField(name string, value ent.Value) error {
 		}
 		m.SetValue(v)
 		return nil
+	case node.FieldParentID:
+		v, ok := value.(int)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetParentID(v)
+		return nil
 	}
 	return fmt.Errorf("unknown Node field %s", name)
 }
@@ -416,7 +466,11 @@ func (m *NodeMutation) AddField(name string, value ent.Value) error {
 // ClearedFields returns all nullable fields that were cleared during this
 // mutation.
 func (m *NodeMutation) ClearedFields() []string {
-	return nil
+	var fields []string
+	if m.FieldCleared(node.FieldParentID) {
+		fields = append(fields, node.FieldParentID)
+	}
+	return fields
 }
 
 // FieldCleared returns a boolean indicating if a field with the given name was
@@ -429,6 +483,11 @@ func (m *NodeMutation) FieldCleared(name string) bool {
 // ClearField clears the value of the field with the given name. It returns an
 // error if the field is not defined in the schema.
 func (m *NodeMutation) ClearField(name string) error {
+	switch name {
+	case node.FieldParentID:
+		m.ClearParentID()
+		return nil
+	}
 	return fmt.Errorf("unknown Node nullable field %s", name)
 }
 
@@ -439,6 +498,9 @@ func (m *NodeMutation) ResetField(name string) error {
 	case node.FieldValue:
 		m.ResetValue()
 		return nil
+	case node.FieldParentID:
+		m.ResetParentID()
+		return nil
 	}
 	return fmt.Errorf("unknown Node field %s", name)
 }

examples/o2mrecur/ent/node.go

@@ -21,10 +21,11 @@ type Node struct {
 	ID int `json:"id,omitempty"`
 	// Value holds the value of the "value" field.
 	Value int `json:"value,omitempty"`
+	// ParentID holds the value of the "parent_id" field.
+	ParentID int `json:"parent_id,omitempty"`
 	// Edges holds the relations/edges for other nodes in the graph.
 	// The values are being populated by the NodeQuery when eager-loading is set.
-	Edges         NodeEdges `json:"edges"`
-	node_children *int
+	Edges NodeEdges `json:"edges"`
 }
 
 // NodeEdges holds the relations/edges for other nodes in the graph.
@@ -65,9 +66,7 @@ func (*Node) scanValues(columns []string) ([]any, error) {
 	values := make([]any, len(columns))
 	for i := range columns {
 		switch columns[i] {
-		case node.FieldID, node.FieldValue:
-			values[i] = new(sql.NullInt64)
-		case node.ForeignKeys[0]: // node_children
+		case node.FieldID, node.FieldValue, node.FieldParentID:
 			values[i] = new(sql.NullInt64)
 		default:
 			return nil, fmt.Errorf("unexpected column %q for type Node", columns[i])
@@ -96,12 +95,11 @@ func (n *Node) assignValues(columns []string, values []any) error {
 			} else if value.Valid {
 				n.Value = int(value.Int64)
 			}
-		case node.ForeignKeys[0]:
+		case node.FieldParentID:
 			if value, ok := values[i].(*sql.NullInt64); !ok {
-				return fmt.Errorf("unexpected type %T for edge-field node_children", value)
+				return fmt.Errorf("unexpected type %T for field parent_id", values[i])
 			} else if value.Valid {
-				n.node_children = new(int)
-				*n.node_children = int(value.Int64)
+				n.ParentID = int(value.Int64)
 			}
 		}
 	}
@@ -143,6 +141,9 @@ func (n *Node) String() string {
 	builder.WriteString(fmt.Sprintf("id=%v, ", n.ID))
 	builder.WriteString("value=")
 	builder.WriteString(fmt.Sprintf("%v", n.Value))
+	builder.WriteString(", ")
+	builder.WriteString("parent_id=")
+	builder.WriteString(fmt.Sprintf("%v", n.ParentID))
 	builder.WriteByte(')')
 	return builder.String()
 }

examples/o2mrecur/ent/node/node.go

@@ -13,6 +13,8 @@ const (
 	FieldID = "id"
 	// FieldValue holds the string denoting the value field in the database.
 	FieldValue = "value"
+	// FieldParentID holds the string denoting the parent_id field in the database.
+	FieldParentID = "parent_id"
 	// EdgeParent holds the string denoting the parent edge name in mutations.
 	EdgeParent = "parent"
 	// EdgeChildren holds the string denoting the children edge name in mutations.
@@ -22,23 +24,18 @@ const (
 	// ParentTable is the table that holds the parent relation/edge.
 	ParentTable = "nodes"
 	// ParentColumn is the table column denoting the parent relation/edge.
-	ParentColumn = "node_children"
+	ParentColumn = "parent_id"
 	// ChildrenTable is the table that holds the children relation/edge.
 	ChildrenTable = "nodes"
 	// ChildrenColumn is the table column denoting the children relation/edge.
-	ChildrenColumn = "node_children"
+	ChildrenColumn = "parent_id"
 )
 
 // Columns holds all SQL columns for node fields.
 var Columns = []string{
 	FieldID,
 	FieldValue,
-}
-
-// ForeignKeys holds the SQL foreign-keys that are owned by the "nodes"
-// table and are not defined as standalone fields in the schema.
-var ForeignKeys = []string{
-	"node_children",
+	FieldParentID,
 }
 
 // ValidColumn reports if the column name is valid (part of the table columns).
@@ -48,10 +45,5 @@ func ValidColumn(column string) bool {
 			return true
 		}
 	}
-	for i := range ForeignKeys {
-		if column == ForeignKeys[i] {
-			return true
-		}
-	}
 	return false
 }

examples/o2mrecur/ent/node/where.go

@@ -62,6 +62,11 @@ func Value(v int) predicate.Node {
 	return predicate.Node(sql.FieldEQ(FieldValue, v))
 }
 
+// ParentID applies equality check predicate on the "parent_id" field. It's identical to ParentIDEQ.
+func ParentID(v int) predicate.Node {
+	return predicate.Node(sql.FieldEQ(FieldParentID, v))
+}
+
 // ValueEQ applies the EQ predicate on the "value" field.
 func ValueEQ(v int) predicate.Node {
 	return predicate.Node(sql.FieldEQ(FieldValue, v))
@@ -102,6 +107,36 @@ func ValueLTE(v int) predicate.Node {
 	return predicate.Node(sql.FieldLTE(FieldValue, v))
 }
 
+// ParentIDEQ applies the EQ predicate on the "parent_id" field.
+func ParentIDEQ(v int) predicate.Node {
+	return predicate.Node(sql.FieldEQ(FieldParentID, v))
+}
+
+// ParentIDNEQ applies the NEQ predicate on the "parent_id" field.
+func ParentIDNEQ(v int) predicate.Node {
+	return predicate.Node(sql.FieldNEQ(FieldParentID, v))
+}
+
+// ParentIDIn applies the In predicate on the "parent_id" field.
+func ParentIDIn(vs ...int) predicate.Node {
+	return predicate.Node(sql.FieldIn(FieldParentID, vs...))
+}
+
+// ParentIDNotIn applies the NotIn predicate on the "parent_id" field.
+func ParentIDNotIn(vs ...int) predicate.Node {
+	return predicate.Node(sql.FieldNotIn(FieldParentID, vs...))
+}
+
+// ParentIDIsNil applies the IsNil predicate on the "parent_id" field.
+func ParentIDIsNil() predicate.Node {
+	return predicate.Node(sql.FieldIsNull(FieldParentID))
+}
+
+// ParentIDNotNil applies the NotNil predicate on the "parent_id" field.
+func ParentIDNotNil() predicate.Node {
+	return predicate.Node(sql.FieldNotNull(FieldParentID))
+}
+
 // HasParent applies the HasEdge predicate on the "parent" edge.
 func HasParent() predicate.Node {
 	return predicate.Node(func(s *sql.Selector) {

examples/o2mrecur/ent/node_create.go

@@ -29,16 +29,16 @@ func (nc *NodeCreate) SetValue(i int) *NodeCreate {
 	return nc
 }
 
-// SetParentID sets the "parent" edge to the Node entity by ID.
-func (nc *NodeCreate) SetParentID(id int) *NodeCreate {
-	nc.mutation.SetParentID(id)
+// SetParentID sets the "parent_id" field.
+func (nc *NodeCreate) SetParentID(i int) *NodeCreate {
+	nc.mutation.SetParentID(i)
 	return nc
 }
 
-// SetNillableParentID sets the "parent" edge to the Node entity by ID if the given value is not nil.
-func (nc *NodeCreate) SetNillableParentID(id *int) *NodeCreate {
-	if id != nil {
-		nc = nc.SetParentID(*id)
+// SetNillableParentID sets the "parent_id" field if the given value is not nil.
+func (nc *NodeCreate) SetNillableParentID(i *int) *NodeCreate {
+	if i != nil {
+		nc.SetParentID(*i)
 	}
 	return nc
 }
@@ -153,7 +153,7 @@ func (nc *NodeCreate) createSpec() (*Node, *sqlgraph.CreateSpec) {
 		for _, k := range nodes {
 			edge.Target.Nodes = append(edge.Target.Nodes, k)
 		}
-		_node.node_children = &nodes[0]
+		_node.ParentID = nodes[0]
 		_spec.Edges = append(_spec.Edges, edge)
 	}
 	if nodes := nc.mutation.ChildrenIDs(); len(nodes) > 0 {

examples/o2mrecur/ent/node_query.go

@@ -28,7 +28,6 @@ type NodeQuery struct {
 	predicates   []predicate.Node
 	withParent   *NodeQuery
 	withChildren *NodeQuery
-	withFKs      bool
 	// intermediate query (i.e. traversal path).
 	sql  *sql.Selector
 	path func(context.Context) (*sql.Selector, error)
@@ -406,19 +405,12 @@ func (nq *NodeQuery) prepareQuery(ctx context.Context) error {
 func (nq *NodeQuery) sqlAll(ctx context.Context, hooks ...queryHook) ([]*Node, error) {
 	var (
 		nodes       = []*Node{}
-		withFKs     = nq.withFKs
 		_spec       = nq.querySpec()
 		loadedTypes = [2]bool{
 			nq.withParent != nil,
 			nq.withChildren != nil,
 		}
 	)
-	if nq.withParent != nil {
-		withFKs = true
-	}
-	if withFKs {
-		_spec.Node.Columns = append(_spec.Node.Columns, node.ForeignKeys...)
-	}
 	_spec.ScanValues = func(columns []string) ([]any, error) {
 		return (*Node).scanValues(nil, columns)
 	}
@@ -457,10 +449,7 @@ func (nq *NodeQuery) loadParent(ctx context.Context, query *NodeQuery, nodes []*
 	ids := make([]int, 0, len(nodes))
 	nodeids := make(map[int][]*Node)
 	for i := range nodes {
-		if nodes[i].node_children == nil {
-			continue
-		}
-		fk := *nodes[i].node_children
+		fk := nodes[i].ParentID
 		if _, ok := nodeids[fk]; !ok {
 			ids = append(ids, fk)
 		}
@@ -477,7 +466,7 @@ func (nq *NodeQuery) loadParent(ctx context.Context, query *NodeQuery, nodes []*
 	for _, n := range neighbors {
 		nodes, ok := nodeids[n.ID]
 		if !ok {
-			return fmt.Errorf(`unexpected foreign-key "node_children" returned %v`, n.ID)
+			return fmt.Errorf(`unexpected foreign-key "parent_id" returned %v`, n.ID)
 		}
 		for i := range nodes {
 			assign(nodes[i], n)
@@ -495,7 +484,6 @@ func (nq *NodeQuery) loadChildren(ctx context.Context, query *NodeQuery, nodes [
 			init(nodes[i])
 		}
 	}
-	query.withFKs = true
 	query.Where(predicate.Node(func(s *sql.Selector) {
 		s.Where(sql.InValues(node.ChildrenColumn, fks...))
 	}))
@@ -504,13 +492,10 @@ func (nq *NodeQuery) loadChildren(ctx context.Context, query *NodeQuery, nodes [
 		return err
 	}
 	for _, n := range neighbors {
-		fk := n.node_children
-		if fk == nil {
-			return fmt.Errorf(`foreign-key "node_children" is nil for node %v`, n.ID)
-		}
-		node, ok := nodeids[*fk]
+		fk := n.ParentID
+		node, ok := nodeids[fk]
 		if !ok {
-			return fmt.Errorf(`unexpected foreign-key "node_children" returned %v for node %v`, *fk, n.ID)
+			return fmt.Errorf(`unexpected foreign-key "parent_id" returned %v for node %v`, fk, n.ID)
 		}
 		assign(node, n)
 	}

examples/o2mrecur/ent/node_update.go

@@ -44,20 +44,26 @@ func (nu *NodeUpdate) AddValue(i int) *NodeUpdate {
 	return nu
 }
 
-// SetParentID sets the "parent" edge to the Node entity by ID.
-func (nu *NodeUpdate) SetParentID(id int) *NodeUpdate {
-	nu.mutation.SetParentID(id)
+// SetParentID sets the "parent_id" field.
+func (nu *NodeUpdate) SetParentID(i int) *NodeUpdate {
+	nu.mutation.SetParentID(i)
 	return nu
 }
 
-// SetNillableParentID sets the "parent" edge to the Node entity by ID if the given value is not nil.
-func (nu *NodeUpdate) SetNillableParentID(id *int) *NodeUpdate {
-	if id != nil {
-		nu = nu.SetParentID(*id)
+// SetNillableParentID sets the "parent_id" field if the given value is not nil.
+func (nu *NodeUpdate) SetNillableParentID(i *int) *NodeUpdate {
+	if i != nil {
+		nu.SetParentID(*i)
 	}
 	return nu
 }
 
+// ClearParentID clears the value of the "parent_id" field.
+func (nu *NodeUpdate) ClearParentID() *NodeUpdate {
+	nu.mutation.ClearParentID()
+	return nu
+}
+
 // SetParent sets the "parent" edge to the Node entity.
 func (nu *NodeUpdate) SetParent(n *Node) *NodeUpdate {
 	return nu.SetParentID(n.ID)
@@ -283,20 +289,26 @@ func (nuo *NodeUpdateOne) AddValue(i int) *NodeUpdateOne {
 	return nuo
 }
 
-// SetParentID sets the "parent" edge to the Node entity by ID.
-func (nuo *NodeUpdateOne) SetParentID(id int) *NodeUpdateOne {
-	nuo.mutation.SetParentID(id)
+// SetParentID sets the "parent_id" field.
+func (nuo *NodeUpdateOne) SetParentID(i int) *NodeUpdateOne {
+	nuo.mutation.SetParentID(i)
 	return nuo
 }
 
-// SetNillableParentID sets the "parent" edge to the Node entity by ID if the given value is not nil.
-func (nuo *NodeUpdateOne) SetNillableParentID(id *int) *NodeUpdateOne {
-	if id != nil {
-		nuo = nuo.SetParentID(*id)
+// SetNillableParentID sets the "parent_id" field if the given value is not nil.
+func (nuo *NodeUpdateOne) SetNillableParentID(i *int) *NodeUpdateOne {
+	if i != nil {
+		nuo.SetParentID(*i)
 	}
 	return nuo
 }
 
+// ClearParentID clears the value of the "parent_id" field.
+func (nuo *NodeUpdateOne) ClearParentID() *NodeUpdateOne {
+	nuo.mutation.ClearParentID()
+	return nuo
+}
+
 // SetParent sets the "parent" edge to the Node entity.
 func (nuo *NodeUpdateOne) SetParent(n *Node) *NodeUpdateOne {
 	return nuo.SetParentID(n.ID)

examples/o2mrecur/ent/schema/node.go

@@ -19,6 +19,8 @@ type Node struct {
 func (Node) Fields() []ent.Field {
 	return []ent.Field{
 		field.Int("value"),
+		field.Int("parent_id").
+			Optional(),
 	}
 }
 
@@ -27,6 +29,7 @@ func (Node) Edges() []ent.Edge {
 	return []ent.Edge{
 		edge.To("children", Node.Type).
 			From("parent").
+			Field("parent_id").
 			Unique(),
 	}
 }

examples/o2mrecur/example_test.go

@@ -32,7 +32,7 @@ func Example_O2MRecur() {
 	// Output:
 	// Tree leafs [1 3 5]
 	// [1 3 5]
-	// Node(id=1, value=2)
+	// Node(id=1, value=2, parent_id=0)
 }
 
 func Do(ctx context.Context, client *ent.Client) error {
@@ -96,7 +96,7 @@ func Do(ctx context.Context, client *ent.Client) error {
 		Where(node.Not(node.HasParent())).
 		OnlyX(ctx)
 	fmt.Println(orphan)
-	// Output: Node(id=1, value=2)
+	// Output: Node(id=1, value=2, parent_id=0)
 
 	return nil
 }

examples/o2orecur/ent/migrate/schema.go

@@ -16,7 +16,7 @@ var (
 	NodesColumns = []*schema.Column{
 		{Name: "id", Type: field.TypeInt, Increment: true},
 		{Name: "value", Type: field.TypeInt},
-		{Name: "node_next", Type: field.TypeInt, Unique: true, Nullable: true},
+		{Name: "prev_id", Type: field.TypeInt, Unique: true, Nullable: true},
 	}
 	// NodesTable holds the schema information for the "nodes" table.
 	NodesTable = &schema.Table{

examples/o2orecur/ent/mutation.go

@@ -203,9 +203,53 @@ func (m *NodeMutation) ResetValue() {
 	m.addvalue = nil
 }
 
-// SetPrevID sets the "prev" edge to the Node entity by id.
-func (m *NodeMutation) SetPrevID(id int) {
-	m.prev = &id
+// SetPrevID sets the "prev_id" field.
+func (m *NodeMutation) SetPrevID(i int) {
+	m.prev = &i
+}
+
+// PrevID returns the value of the "prev_id" field in the mutation.
+func (m *NodeMutation) PrevID() (r int, exists bool) {
+	v := m.prev
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldPrevID returns the old "prev_id" field's value of the Node entity.
+// If the Node object wasn't provided to the builder, the object is fetched from the database.
+// An error is returned if the mutation operation is not UpdateOne, or the database query fails.
+func (m *NodeMutation) OldPrevID(ctx context.Context) (v int, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldPrevID is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldPrevID requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldPrevID: %w", err)
+	}
+	return oldValue.PrevID, nil
+}
+
+// ClearPrevID clears the value of the "prev_id" field.
+func (m *NodeMutation) ClearPrevID() {
+	m.prev = nil
+	m.clearedFields[node.FieldPrevID] = struct{}{}
+}
+
+// PrevIDCleared returns if the "prev_id" field was cleared in this mutation.
+func (m *NodeMutation) PrevIDCleared() bool {
+	_, ok := m.clearedFields[node.FieldPrevID]
+	return ok
+}
+
+// ResetPrevID resets all changes to the "prev_id" field.
+func (m *NodeMutation) ResetPrevID() {
+	m.prev = nil
+	delete(m.clearedFields, node.FieldPrevID)
 }
 
 // ClearPrev clears the "prev" edge to the Node entity.
@@ -215,15 +259,7 @@ func (m *NodeMutation) ClearPrev() {
 
 // PrevCleared reports if the "prev" edge to the Node entity was cleared.
 func (m *NodeMutation) PrevCleared() bool {
-	return m.clearedprev
-}
-
-// PrevID returns the "prev" edge ID in the mutation.
-func (m *NodeMutation) PrevID() (id int, exists bool) {
-	if m.prev != nil {
-		return *m.prev, true
-	}
-	return
+	return m.PrevIDCleared() || m.clearedprev
 }
 
 // PrevIDs returns the "prev" edge IDs in the mutation.
@@ -315,10 +351,13 @@ func (m *NodeMutation) Type() string {
 // order to get all numeric fields that were incremented/decremented, call
 // AddedFields().
 func (m *NodeMutation) Fields() []string {
-	fields := make([]string, 0, 1)
+	fields := make([]string, 0, 2)
 	if m.value != nil {
 		fields = append(fields, node.FieldValue)
 	}
+	if m.prev != nil {
+		fields = append(fields, node.FieldPrevID)
+	}
 	return fields
 }
 
@@ -329,6 +368,8 @@ func (m *NodeMutation) Field(name string) (ent.Value, bool) {
 	switch name {
 	case node.FieldValue:
 		return m.Value()
+	case node.FieldPrevID:
+		return m.PrevID()
 	}
 	return nil, false
 }
@@ -340,6 +381,8 @@ func (m *NodeMutation) OldField(ctx context.Context, name string) (ent.Value, er
 	switch name {
 	case node.FieldValue:
 		return m.OldValue(ctx)
+	case node.FieldPrevID:
+		return m.OldPrevID(ctx)
 	}
 	return nil, fmt.Errorf("unknown Node field %s", name)
 }
@@ -356,6 +399,13 @@ func (m *NodeMutation) SetField(name string, value ent.Value) error {
 		}
 		m.SetValue(v)
 		return nil
+	case node.FieldPrevID:
+		v, ok := value.(int)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetPrevID(v)
+		return nil
 	}
 	return fmt.Errorf("unknown Node field %s", name)
 }
@@ -400,7 +450,11 @@ func (m *NodeMutation) AddField(name string, value ent.Value) error {
 // ClearedFields returns all nullable fields that were cleared during this
 // mutation.
 func (m *NodeMutation) ClearedFields() []string {
-	return nil
+	var fields []string
+	if m.FieldCleared(node.FieldPrevID) {
+		fields = append(fields, node.FieldPrevID)
+	}
+	return fields
 }
 
 // FieldCleared returns a boolean indicating if a field with the given name was
@@ -413,6 +467,11 @@ func (m *NodeMutation) FieldCleared(name string) bool {
 // ClearField clears the value of the field with the given name. It returns an
 // error if the field is not defined in the schema.
 func (m *NodeMutation) ClearField(name string) error {
+	switch name {
+	case node.FieldPrevID:
+		m.ClearPrevID()
+		return nil
+	}
 	return fmt.Errorf("unknown Node nullable field %s", name)
 }
 
@@ -423,6 +482,9 @@ func (m *NodeMutation) ResetField(name string) error {
 	case node.FieldValue:
 		m.ResetValue()
 		return nil
+	case node.FieldPrevID:
+		m.ResetPrevID()
+		return nil
 	}
 	return fmt.Errorf("unknown Node field %s", name)
 }

examples/o2orecur/ent/node.go

@@ -21,10 +21,11 @@ type Node struct {
 	ID int `json:"id,omitempty"`
 	// Value holds the value of the "value" field.
 	Value int `json:"value,omitempty"`
+	// PrevID holds the value of the "prev_id" field.
+	PrevID int `json:"prev_id,omitempty"`
 	// Edges holds the relations/edges for other nodes in the graph.
 	// The values are being populated by the NodeQuery when eager-loading is set.
-	Edges     NodeEdges `json:"edges"`
-	node_next *int
+	Edges NodeEdges `json:"edges"`
 }
 
 // NodeEdges holds the relations/edges for other nodes in the graph.
@@ -69,9 +70,7 @@ func (*Node) scanValues(columns []string) ([]any, error) {
 	values := make([]any, len(columns))
 	for i := range columns {
 		switch columns[i] {
-		case node.FieldID, node.FieldValue:
-			values[i] = new(sql.NullInt64)
-		case node.ForeignKeys[0]: // node_next
+		case node.FieldID, node.FieldValue, node.FieldPrevID:
 			values[i] = new(sql.NullInt64)
 		default:
 			return nil, fmt.Errorf("unexpected column %q for type Node", columns[i])
@@ -100,12 +99,11 @@ func (n *Node) assignValues(columns []string, values []any) error {
 			} else if value.Valid {
 				n.Value = int(value.Int64)
 			}
-		case node.ForeignKeys[0]:
+		case node.FieldPrevID:
 			if value, ok := values[i].(*sql.NullInt64); !ok {
-				return fmt.Errorf("unexpected type %T for edge-field node_next", value)
+				return fmt.Errorf("unexpected type %T for field prev_id", values[i])
 			} else if value.Valid {
-				n.node_next = new(int)
-				*n.node_next = int(value.Int64)
+				n.PrevID = int(value.Int64)
 			}
 		}
 	}
@@ -147,6 +145,9 @@ func (n *Node) String() string {
 	builder.WriteString(fmt.Sprintf("id=%v, ", n.ID))
 	builder.WriteString("value=")
 	builder.WriteString(fmt.Sprintf("%v", n.Value))
+	builder.WriteString(", ")
+	builder.WriteString("prev_id=")
+	builder.WriteString(fmt.Sprintf("%v", n.PrevID))
 	builder.WriteByte(')')
 	return builder.String()
 }

examples/o2orecur/ent/node/node.go

@@ -13,6 +13,8 @@ const (
 	FieldID = "id"
 	// FieldValue holds the string denoting the value field in the database.
 	FieldValue = "value"
+	// FieldPrevID holds the string denoting the prev_id field in the database.
+	FieldPrevID = "prev_id"
 	// EdgePrev holds the string denoting the prev edge name in mutations.
 	EdgePrev = "prev"
 	// EdgeNext holds the string denoting the next edge name in mutations.
@@ -22,23 +24,18 @@ const (
 	// PrevTable is the table that holds the prev relation/edge.
 	PrevTable = "nodes"
 	// PrevColumn is the table column denoting the prev relation/edge.
-	PrevColumn = "node_next"
+	PrevColumn = "prev_id"
 	// NextTable is the table that holds the next relation/edge.
 	NextTable = "nodes"
 	// NextColumn is the table column denoting the next relation/edge.
-	NextColumn = "node_next"
+	NextColumn = "prev_id"
 )
 
 // Columns holds all SQL columns for node fields.
 var Columns = []string{
 	FieldID,
 	FieldValue,
-}
-
-// ForeignKeys holds the SQL foreign-keys that are owned by the "nodes"
-// table and are not defined as standalone fields in the schema.
-var ForeignKeys = []string{
-	"node_next",
+	FieldPrevID,
 }
 
 // ValidColumn reports if the column name is valid (part of the table columns).
@@ -48,10 +45,5 @@ func ValidColumn(column string) bool {
 			return true
 		}
 	}
-	for i := range ForeignKeys {
-		if column == ForeignKeys[i] {
-			return true
-		}
-	}
 	return false
 }

examples/o2orecur/ent/node/where.go

@@ -62,6 +62,11 @@ func Value(v int) predicate.Node {
 	return predicate.Node(sql.FieldEQ(FieldValue, v))
 }
 
+// PrevID applies equality check predicate on the "prev_id" field. It's identical to PrevIDEQ.
+func PrevID(v int) predicate.Node {
+	return predicate.Node(sql.FieldEQ(FieldPrevID, v))
+}
+
 // ValueEQ applies the EQ predicate on the "value" field.
 func ValueEQ(v int) predicate.Node {
 	return predicate.Node(sql.FieldEQ(FieldValue, v))
@@ -102,6 +107,36 @@ func ValueLTE(v int) predicate.Node {
 	return predicate.Node(sql.FieldLTE(FieldValue, v))
 }
 
+// PrevIDEQ applies the EQ predicate on the "prev_id" field.
+func PrevIDEQ(v int) predicate.Node {
+	return predicate.Node(sql.FieldEQ(FieldPrevID, v))
+}
+
+// PrevIDNEQ applies the NEQ predicate on the "prev_id" field.
+func PrevIDNEQ(v int) predicate.Node {
+	return predicate.Node(sql.FieldNEQ(FieldPrevID, v))
+}
+
+// PrevIDIn applies the In predicate on the "prev_id" field.
+func PrevIDIn(vs ...int) predicate.Node {
+	return predicate.Node(sql.FieldIn(FieldPrevID, vs...))
+}
+
+// PrevIDNotIn applies the NotIn predicate on the "prev_id" field.
+func PrevIDNotIn(vs ...int) predicate.Node {
+	return predicate.Node(sql.FieldNotIn(FieldPrevID, vs...))
+}
+
+// PrevIDIsNil applies the IsNil predicate on the "prev_id" field.
+func PrevIDIsNil() predicate.Node {
+	return predicate.Node(sql.FieldIsNull(FieldPrevID))
+}
+
+// PrevIDNotNil applies the NotNil predicate on the "prev_id" field.
+func PrevIDNotNil() predicate.Node {
+	return predicate.Node(sql.FieldNotNull(FieldPrevID))
+}
+
 // HasPrev applies the HasEdge predicate on the "prev" edge.
 func HasPrev() predicate.Node {
 	return predicate.Node(func(s *sql.Selector) {

examples/o2orecur/ent/node_create.go

@@ -29,16 +29,16 @@ func (nc *NodeCreate) SetValue(i int) *NodeCreate {
 	return nc
 }
 
-// SetPrevID sets the "prev" edge to the Node entity by ID.
-func (nc *NodeCreate) SetPrevID(id int) *NodeCreate {
-	nc.mutation.SetPrevID(id)
+// SetPrevID sets the "prev_id" field.
+func (nc *NodeCreate) SetPrevID(i int) *NodeCreate {
+	nc.mutation.SetPrevID(i)
 	return nc
 }
 
-// SetNillablePrevID sets the "prev" edge to the Node entity by ID if the given value is not nil.
-func (nc *NodeCreate) SetNillablePrevID(id *int) *NodeCreate {
-	if id != nil {
-		nc = nc.SetPrevID(*id)
+// SetNillablePrevID sets the "prev_id" field if the given value is not nil.
+func (nc *NodeCreate) SetNillablePrevID(i *int) *NodeCreate {
+	if i != nil {
+		nc.SetPrevID(*i)
 	}
 	return nc
 }
@@ -157,7 +157,7 @@ func (nc *NodeCreate) createSpec() (*Node, *sqlgraph.CreateSpec) {
 		for _, k := range nodes {
 			edge.Target.Nodes = append(edge.Target.Nodes, k)
 		}
-		_node.node_next = &nodes[0]
+		_node.PrevID = nodes[0]
 		_spec.Edges = append(_spec.Edges, edge)
 	}
 	if nodes := nc.mutation.NextIDs(); len(nodes) > 0 {

examples/o2orecur/ent/node_query.go

@@ -28,7 +28,6 @@ type NodeQuery struct {
 	predicates []predicate.Node
 	withPrev   *NodeQuery
 	withNext   *NodeQuery
-	withFKs    bool
 	// intermediate query (i.e. traversal path).
 	sql  *sql.Selector
 	path func(context.Context) (*sql.Selector, error)
@@ -406,19 +405,12 @@ func (nq *NodeQuery) prepareQuery(ctx context.Context) error {
 func (nq *NodeQuery) sqlAll(ctx context.Context, hooks ...queryHook) ([]*Node, error) {
 	var (
 		nodes       = []*Node{}
-		withFKs     = nq.withFKs
 		_spec       = nq.querySpec()
 		loadedTypes = [2]bool{
 			nq.withPrev != nil,
 			nq.withNext != nil,
 		}
 	)
-	if nq.withPrev != nil {
-		withFKs = true
-	}
-	if withFKs {
-		_spec.Node.Columns = append(_spec.Node.Columns, node.ForeignKeys...)
-	}
 	_spec.ScanValues = func(columns []string) ([]any, error) {
 		return (*Node).scanValues(nil, columns)
 	}
@@ -456,10 +448,7 @@ func (nq *NodeQuery) loadPrev(ctx context.Context, query *NodeQuery, nodes []*No
 	ids := make([]int, 0, len(nodes))
 	nodeids := make(map[int][]*Node)
 	for i := range nodes {
-		if nodes[i].node_next == nil {
-			continue
-		}
-		fk := *nodes[i].node_next
+		fk := nodes[i].PrevID
 		if _, ok := nodeids[fk]; !ok {
 			ids = append(ids, fk)
 		}
@@ -476,7 +465,7 @@ func (nq *NodeQuery) loadPrev(ctx context.Context, query *NodeQuery, nodes []*No
 	for _, n := range neighbors {
 		nodes, ok := nodeids[n.ID]
 		if !ok {
-			return fmt.Errorf(`unexpected foreign-key "node_next" returned %v`, n.ID)
+			return fmt.Errorf(`unexpected foreign-key "prev_id" returned %v`, n.ID)
 		}
 		for i := range nodes {
 			assign(nodes[i], n)
@@ -491,7 +480,6 @@ func (nq *NodeQuery) loadNext(ctx context.Context, query *NodeQuery, nodes []*No
 		fks = append(fks, nodes[i].ID)
 		nodeids[nodes[i].ID] = nodes[i]
 	}
-	query.withFKs = true
 	query.Where(predicate.Node(func(s *sql.Selector) {
 		s.Where(sql.InValues(node.NextColumn, fks...))
 	}))
@@ -500,13 +488,10 @@ func (nq *NodeQuery) loadNext(ctx context.Context, query *NodeQuery, nodes []*No
 		return err
 	}
 	for _, n := range neighbors {
-		fk := n.node_next
-		if fk == nil {
-			return fmt.Errorf(`foreign-key "node_next" is nil for node %v`, n.ID)
-		}
-		node, ok := nodeids[*fk]
+		fk := n.PrevID
+		node, ok := nodeids[fk]
 		if !ok {
-			return fmt.Errorf(`unexpected foreign-key "node_next" returned %v for node %v`, *fk, n.ID)
+			return fmt.Errorf(`unexpected foreign-key "prev_id" returned %v for node %v`, fk, n.ID)
 		}
 		assign(node, n)
 	}

examples/o2orecur/ent/node_update.go

@@ -44,20 +44,26 @@ func (nu *NodeUpdate) AddValue(i int) *NodeUpdate {
 	return nu
 }
 
-// SetPrevID sets the "prev" edge to the Node entity by ID.
-func (nu *NodeUpdate) SetPrevID(id int) *NodeUpdate {
-	nu.mutation.SetPrevID(id)
+// SetPrevID sets the "prev_id" field.
+func (nu *NodeUpdate) SetPrevID(i int) *NodeUpdate {
+	nu.mutation.SetPrevID(i)
 	return nu
 }
 
-// SetNillablePrevID sets the "prev" edge to the Node entity by ID if the given value is not nil.
-func (nu *NodeUpdate) SetNillablePrevID(id *int) *NodeUpdate {
-	if id != nil {
-		nu = nu.SetPrevID(*id)
+// SetNillablePrevID sets the "prev_id" field if the given value is not nil.
+func (nu *NodeUpdate) SetNillablePrevID(i *int) *NodeUpdate {
+	if i != nil {
+		nu.SetPrevID(*i)
 	}
 	return nu
 }
 
+// ClearPrevID clears the value of the "prev_id" field.
+func (nu *NodeUpdate) ClearPrevID() *NodeUpdate {
+	nu.mutation.ClearPrevID()
+	return nu
+}
+
 // SetPrev sets the "prev" edge to the Node entity.
 func (nu *NodeUpdate) SetPrev(n *Node) *NodeUpdate {
 	return nu.SetPrevID(n.ID)
@@ -253,20 +259,26 @@ func (nuo *NodeUpdateOne) AddValue(i int) *NodeUpdateOne {
 	return nuo
 }
 
-// SetPrevID sets the "prev" edge to the Node entity by ID.
-func (nuo *NodeUpdateOne) SetPrevID(id int) *NodeUpdateOne {
-	nuo.mutation.SetPrevID(id)
+// SetPrevID sets the "prev_id" field.
+func (nuo *NodeUpdateOne) SetPrevID(i int) *NodeUpdateOne {
+	nuo.mutation.SetPrevID(i)
 	return nuo
 }
 
-// SetNillablePrevID sets the "prev" edge to the Node entity by ID if the given value is not nil.
-func (nuo *NodeUpdateOne) SetNillablePrevID(id *int) *NodeUpdateOne {
-	if id != nil {
-		nuo = nuo.SetPrevID(*id)
+// SetNillablePrevID sets the "prev_id" field if the given value is not nil.
+func (nuo *NodeUpdateOne) SetNillablePrevID(i *int) *NodeUpdateOne {
+	if i != nil {
+		nuo.SetPrevID(*i)
 	}
 	return nuo
 }
 
+// ClearPrevID clears the value of the "prev_id" field.
+func (nuo *NodeUpdateOne) ClearPrevID() *NodeUpdateOne {
+	nuo.mutation.ClearPrevID()
+	return nuo
+}
+
 // SetPrev sets the "prev" edge to the Node entity.
 func (nuo *NodeUpdateOne) SetPrev(n *Node) *NodeUpdateOne {
 	return nuo.SetPrevID(n.ID)

examples/o2orecur/ent/schema/node.go

@@ -19,6 +19,8 @@ type Node struct {
 func (Node) Fields() []ent.Field {
 	return []ent.Field{
 		field.Int("value"),
+		field.Int("prev_id").
+			Optional(),
 	}
 }
 
@@ -28,6 +30,7 @@ func (Node) Edges() []ent.Edge {
 		edge.To("next", Node.Type).
 			Unique().
 			From("prev").
+			Field("prev_id").
 			Unique(),
 	}
 }