Reset negative count on hand in existing non backorderable stock items

db/migrate/20200514174526_reset_negative_nonbackorderable_count_on_hand_in_stock_items.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+class ResetNegativeNonbackorderableCountOnHandInStockItems < ActiveRecord::Migration
+  module Spree
+    class StockItem < ActiveRecord::Base
+      self.table_name = "spree_stock_items"
+    end
+  end
+
+  def up
+    Spree::StockItem.where(backorderable: false)
+      .where("count_on_hand < 0")
+      .update_all(count_on_hand: 0)
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end