FEATURE: Add post edits count to user activity (#13495)

db/migrate/20210708035525_add_user_id_index_to_post_revisions.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddUserIdIndexToPostRevisions < ActiveRecord::Migration[6.1]
+  def change
+    add_index :post_revisions, :user_id
+  end
+end

db/migrate/20210708035538_add_post_edits_count_to_user_stats.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+class AddPostEditsCountToUserStats < ActiveRecord::Migration[6.1]
+  disable_ddl_transaction!
+  BATCH_SIZE = 30_000
+
+  def up
+    add_column :user_stats, :post_edits_count, :integer
+
+    loop do
+      count = DB.exec(<<~SQL, batch_size: BATCH_SIZE)
+        UPDATE user_stats us
+        SET post_edits_count = editor.edits_count
+        FROM (
+          SELECT COUNT(editor.id) AS edits_count, editor.id AS id
+          FROM post_revisions pr JOIN users editor ON editor.id = pr.user_id
+          JOIN user_stats us ON us.user_id = editor.id
+          WHERE us.post_edits_count IS NULL AND pr.user_id IS NOT NULL
+          GROUP BY editor.id
+          LIMIT :batch_size
+        ) editor
+        WHERE editor.id = us.user_id;
+      SQL
+      break if count == 0
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end