diff --git a/model/basket.go b/model/basket.go
index 3161c4e..766b646 100644
--- a/model/basket.go
+++ b/model/basket.go
@@ -8,7 +8,7 @@ type BasketModel struct {
 	ID        string           `db:"id" json:"id"`
 	State     string           `db:"state" json:"state"`
 	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at"`
+	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
 }
 
 type BasketItemModel struct {
@@ -18,5 +18,5 @@ type BasketItemModel struct {
 	Quantity  int              `db:"quantity" json:"quantity"`
 	Price     float64          `db:"price" json:"price"`
 	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at"`
+	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
 }
diff --git a/model/catalog.go b/model/catalog.go
index ce74a43..cc8f4b9 100644
--- a/model/catalog.go
+++ b/model/catalog.go
@@ -8,5 +8,5 @@ type ProductModel struct {
 	Name      string           `db:"name"`
 	Price     float64          `db:"price"`
 	CreatedAt pgtype.Timestamp `db:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at"`
+	UpdatedAt pgtype.Timestamp `db:"updated_at,omitempty"`
 }
diff --git a/model/order.go b/model/order.go
index 73dab4b..042ea97 100644
--- a/model/order.go
+++ b/model/order.go
@@ -6,7 +6,7 @@ type OrderModel struct {
 	ID        string           `db:"id" json:"id"`
 	State     string           `db:"state" json:"state"`
 	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at"`
+	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
 }
 
 type OrderItemModel struct {
@@ -16,5 +16,5 @@ type OrderItemModel struct {
 	Quantity  int              `db:"quantity" json:"quantity"`
 	Price     float64          `db:"price" json:"price"`
 	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at"`
+	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
 }