fixed 发贴内容长度增加longtext

db/migrate/20230814055132_change_memos_content_size.rb

@@ -1,5 +1,5 @@
 class ChangeMemosContentSize < ActiveRecord::Migration[5.2]
   def change
-    execute "ALTER TABLE memos MODIFY COLUMN `content` longtext;"
+    execute("ALTER TABLE `memos` MODIFY `content` longtext CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;")
   end
 end