diff --git a/db/migrate/20210202052337_migrate_variant_unit_values.rb b/db/migrate/20210202052337_migrate_variant_unit_values.rb
index 3c63a919bb..3dd5da4805 100644
--- a/db/migrate/20210202052337_migrate_variant_unit_values.rb
+++ b/db/migrate/20210202052337_migrate_variant_unit_values.rb
@@ -2,15 +2,28 @@ class MigrateVariantUnitValues < ActiveRecord::Migration
   def up
     Spree::Variant.includes(:product).where(
       spree_products: { variant_unit: "items" },
-      spree_variants: { unit_value: nil }
+      spree_variants: { unit_value: [nil, Float::NAN] }
     ).find_each do |variant|
       variant.unit_value = 1
       variant.save
     end
+    Spree::Variant.includes(:product).where(
+      spree_products: { variant_unit: "items" },
+      spree_variants: { weight: [nil, Float::NAN] }
+    ).find_each do |variant|
+      variant.weight = 0
+      variant.save
+    end
     change_column_null :spree_variants, :unit_value, false, 1
     change_column_null :spree_variants, :weight, false, 0.0
+    execute "ALTER TABLE spree_variants ADD CONSTRAINT check_unit_value_for_nan CHECK (unit_value <> 'NaN')"
+    execute "ALTER TABLE spree_variants ADD CONSTRAINT check_weight_for_nan CHECK (weight <> 'NaN')"
   end
 
   def down
+    change_column_null :spree_variants, :unit_value, true
+    change_column_null :spree_variants, :weight, true
+    execute "ALTER TABLE spree_variants DROP CONSTRAINT check_unit_value_for_nan"
+    execute "ALTER TABLE spree_variants DROP CONSTRAINT check_weight_for_nan"
   end
 end
diff --git a/db/schema.rb b/db/schema.rb
index 82647c958b..9c4b067bd4 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -1061,7 +1061,7 @@ ActiveRecord::Schema.define(version: 20210202052337) do
 
   create_table "spree_variants", force: :cascade do |t|
     t.string   "sku",              limit: 255,                         default: "",    null: false
-    t.decimal  "weight",                       precision: 8, scale: 2
+    t.decimal  "weight",                       precision: 8, scale: 2,                 null: false
     t.decimal  "height",                       precision: 8, scale: 2
     t.decimal  "width",                        precision: 8, scale: 2
     t.decimal  "depth",                        precision: 8, scale: 2