diff --git a/app/models/conversation.rb b/app/models/conversation.rb
index efd3aa963..be9bf26ab 100644
--- a/app/models/conversation.rb
+++ b/app/models/conversation.rb
@@ -7,12 +7,12 @@
 #  agent_last_seen_at    :datetime
 #  contact_last_seen_at  :datetime
 #  identifier            :string
-#  last_activity_at      :datetime
+#  last_activity_at      :datetime         not null
 #  locked                :boolean          default(FALSE)
 #  status                :integer          default("open"), not null
 #  uuid                  :uuid             not null
-#  created_at            :datetime
-#  updated_at            :datetime
+#  created_at            :datetime         not null
+#  updated_at            :datetime         not null
 #  account_id            :integer          not null
 #  assignee_id           :integer
 #  contact_id            :bigint
diff --git a/db/migrate/20210105185632_enable_pg_stats_extention.rb b/db/migrate/20210105185632_enable_pg_stats_extention.rb
new file mode 100644
index 000000000..f03b0dc20
--- /dev/null
+++ b/db/migrate/20210105185632_enable_pg_stats_extention.rb
@@ -0,0 +1,5 @@
+class EnablePgStatsExtention < ActiveRecord::Migration[6.0]
+  def change
+    enable_extension 'pg_stat_statements'
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index e7c0eb71d..63aa46271 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2020_11_25_123131) do
+ActiveRecord::Schema.define(version: 2021_01_05_185632) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_stat_statements"
@@ -219,8 +219,8 @@ ActiveRecord::Schema.define(version: 2020_11_25_123131) do
     t.integer "inbox_id", null: false
     t.integer "status", default: 0, null: false
     t.integer "assignee_id"
-    t.datetime "created_at"
-    t.datetime "updated_at"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
     t.bigint "contact_id"
     t.integer "display_id", null: false
     t.datetime "contact_last_seen_at"
@@ -230,7 +230,7 @@ ActiveRecord::Schema.define(version: 2020_11_25_123131) do
     t.bigint "contact_inbox_id"
     t.uuid "uuid", default: -> { "gen_random_uuid()" }, null: false
     t.string "identifier"
-    t.datetime "last_activity_at", default: -> { "CURRENT_TIMESTAMP" }
+    t.datetime "last_activity_at", default: -> { "CURRENT_TIMESTAMP" }, null: false
     t.index ["account_id", "display_id"], name: "index_conversations_on_account_id_and_display_id", unique: true
     t.index ["account_id"], name: "index_conversations_on_account_id"
     t.index ["contact_inbox_id"], name: "index_conversations_on_contact_inbox_id"
@@ -456,9 +456,11 @@ ActiveRecord::Schema.define(version: 2020_11_25_123131) do
     t.index ["taggable_id", "taggable_type", "context"], name: "index_taggings_on_taggable_id_and_taggable_type_and_context"
     t.index ["taggable_id", "taggable_type", "tagger_id", "context"], name: "taggings_idy"
     t.index ["taggable_id"], name: "index_taggings_on_taggable_id"
+    t.index ["taggable_type", "taggable_id"], name: "index_taggings_on_taggable_type_and_taggable_id"
     t.index ["taggable_type"], name: "index_taggings_on_taggable_type"
     t.index ["tagger_id", "tagger_type"], name: "index_taggings_on_tagger_id_and_tagger_type"
     t.index ["tagger_id"], name: "index_taggings_on_tagger_id"
+    t.index ["tagger_type", "tagger_id"], name: "index_taggings_on_tagger_type_and_tagger_id"
   end
 
   create_table "tags", id: :serial, force: :cascade do |t|