Method Only

ent/entity_query.go:181–194

Only returns a single Entity entity found by the query, ensuring it only returns one. Returns a *NotSingularError when more than one Entity entity is found. Returns a *NotFoundError when no Entity entities are found.

(ctx context.Context)

// Returns a *NotSingularError when more than one Entity entity is found.
// Returns a *NotFoundError when no Entity entities are found.
func (eq *EntityQuery) Only(ctx context.Context) (*Entity, error) {
	nodes, err := eq.Limit(2).All(setContextOp(ctx, eq.ctx, "Only"))
	if err != nil {
		return nil, err
	}
	switch len(nodes) {
	case 1:
		return nodes[0], nil
	case 0:
		return nil, &NotFoundError{entity.Label}
	default:
		return nil, &NotSingularError{entity.Label}
	}
}

// OnlyX is like Only, but panics if an error occurs.
func (eq *EntityQuery) OnlyX(ctx context.Context) *Entity {