Change the project_id index to be unique on vulnerability_statistics

db/migrate/20200702123805_change_project_id_index_to_be_unique_on_vulnerability_statistics_table.rb

+# frozen_string_literal: true
+
+class ChangeProjectIdIndexToBeUniqueOnVulnerabilityStatisticsTable < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  INDEX_NAME = 'index_vulnerability_statistics_on_unique_project_id'
+
+  def up
+    remove_index :vulnerability_statistics, :project_id # rubocop:disable Migration/RemoveIndex (table is empty)
+    add_index :vulnerability_statistics, :project_id, name: INDEX_NAME, unique: true # rubocop:disable Migration/AddIndex (table is empty)
+  end
+
+  def down
+    remove_index :vulnerability_statistics, name: INDEX_NAME # rubocop:disable Migration/RemoveIndex (table is empty)
+    add_index :vulnerability_statistics, :project_id # rubocop:disable Migration/AddIndex (table is empty)
+  end
+end

db/structure.sql

@@ -20353,7 +20353,7 @@ CREATE UNIQUE INDEX index_vulnerability_scanners_on_project_id_and_external_id O
 
 CREATE INDEX index_vulnerability_statistics_on_letter_grade ON public.vulnerability_statistics USING btree (letter_grade);
 
-CREATE INDEX index_vulnerability_statistics_on_project_id ON public.vulnerability_statistics USING btree (project_id);
+CREATE UNIQUE INDEX index_vulnerability_statistics_on_unique_project_id ON public.vulnerability_statistics USING btree (project_id);
 
 CREATE UNIQUE INDEX index_vulnerability_user_mentions_on_note_id ON public.vulnerability_user_mentions USING btree (note_id) WHERE (note_id IS NOT NULL);
 
@@ -23532,5 +23532,6 @@ COPY "schema_migrations" (version) FROM STDIN;
 20200625082258
 20200625190458
 20200626130220
+20200702123805
 \.