init project

db/migrate/20200103062807_create_issue_depends.rb

@@ -0,0 +1,12 @@
+class CreateIssueDepends < ActiveRecord::Migration[5.2]
+  def change
+    create_table :issue_depends do |t|
+      t.integer :user_id
+      t.integer :issue_id
+      t.integer :depend_issue_id
+      t.timestamps
+    end
+
+    add_index :issue_depends, [:user_id, :issue_id, :depend_issue_id]
+  end
+end