diff --git a/config/initializers/_lograge.rb b/config/initializers/_lograge.rb
index f8cc17dfc..eb6693412 100644
--- a/config/initializers/_lograge.rb
+++ b/config/initializers/_lograge.rb
@@ -23,4 +23,4 @@
       uid: event.payload[:uid],
     }
   end
-end
\ No newline at end of file
+end
diff --git a/db/migrate/20200121101841_add_foreign_key_to_events.rb b/db/migrate/20200121101841_add_foreign_key_to_events.rb
deleted file mode 100644
index 343230fb3..000000000
--- a/db/migrate/20200121101841_add_foreign_key_to_events.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-# frozen_string_literal: true
-
-class AddForeignKeyToEvents < ActiveRecord::Migration[5.2]
-  def change
-    add_column :events, :doi_id, :text
-    add_index :events, [:doi_id, :relation_type_id], name: "index_events_on_doi_id", length: { doi_id: 100, relation_type_id: 191 }
-  end
-end
diff --git a/db/migrate/20200122153731_add_globus_uuid.rb b/db/migrate/20200122153731_add_globus_uuid.rb
index 7c35a75c8..87bc581d1 100644
--- a/db/migrate/20200122153731_add_globus_uuid.rb
+++ b/db/migrate/20200122153731_add_globus_uuid.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class AddGlobusUuid < ActiveRecord::Migration[5.2]
   def change
     add_column :datacentre, :globus_uuid, :string, limit: 191
diff --git a/db/migrate/20200131180609_add_events_properties.rb b/db/migrate/20200131180609_add_events_properties.rb
new file mode 100644
index 000000000..26805d225
--- /dev/null
+++ b/db/migrate/20200131180609_add_events_properties.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+class AddEventsProperties < ActiveRecord::Migration[5.2]
+  def change
+    add_column :events, :source_doi, :text
+    add_column :events, :target_doi, :text
+    add_column :events, :source_relation_type_id, :string, limit: 191
+    add_column :events, :target_relation_type_id, :string, limit: 191
+    add_index :events, [:source_doi, :source_relation_type_id], name: "index_events_on_source_doi", length: { source_doi: 100, source_relation_type_id: 191 }
+    add_index :events, [:target_doi, :target_relation_type_id], name: "index_events_on_target_doi", length: { target_doi: 100, target_relation_type_id: 191 }
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 5b195b293..8533b731b 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_01_22_153731) do
+ActiveRecord::Schema.define(version: 2020_01_31_180609) do
 
   create_table "active_storage_attachments", options: "ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin", force: :cascade do |t|
     t.string "name", limit: 191, null: false
@@ -229,7 +229,6 @@
     t.text "uuid", null: false
     t.text "subj_id", null: false
     t.text "obj_id"
-    t.string "source_id", limit: 191
     t.string "aasm_state"
     t.string "state_event"
     t.text "callback"
@@ -246,10 +245,16 @@
     t.integer "total", default: 1
     t.string "license", limit: 191
     t.text "doi_id"
+    t.text "source_doi"
+    t.text "target_doi"
+    t.string "source_relation_type_id", limit: 191
+    t.string "target_relation_type_id", limit: 191
     t.index ["created_at", "indexed_at", "updated_at"], name: "index_events_on_created_indexed_updated"
+    t.index ["created_at"], name: "index_events_on_source_id_created_at"
     t.index ["relation_type_id"], name: "index_events_on_doi_id"
-    t.index ["source_id", "created_at"], name: "index_events_on_source_id_created_at"
-    t.index ["subj_id", "obj_id", "source_id", "relation_type_id"], name: "index_events_on_multiple_columns", unique: true, length: { subj_id: 191, obj_id: 191 }
+    t.index ["source_doi", "source_relation_type_id"], name: "index_events_on_source_doi", length: { source_doi: 100 }
+    t.index ["subj_id", "obj_id", "relation_type_id"], name: "index_events_on_multiple_columns", unique: true, length: { subj_id: 191, obj_id: 191 }
+    t.index ["target_doi", "target_relation_type_id"], name: "index_events_on_target_doi", length: { target_doi: 100 }
     t.index ["updated_at"], name: "index_events_on_updated_at"
     t.index ["uuid"], name: "index_events_on_uuid", unique: true, length: 36
   end