Add the TABLE_SCHEMA condition to the SELECT statement in table_comment (#25945)

[Rafael Mendonça França + Takeshi AKIMA]

activerecord/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Fix the SELECT statement in `#table_comment` for MySQL.
+
+    *Takeshi Akima*
+
 *   Virtual attributes will no longer raise when read on models loaded from the
     database
 

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -413,7 +413,8 @@ module ActiveRecord
         select_value(<<-SQL.strip_heredoc, 'SCHEMA')
           SELECT table_comment
           FROM information_schema.tables
-          WHERE table_name=#{quote(table_name)}
+          WHERE table_schema=#{quote(current_database)}
+            AND table_name=#{quote(table_name)}
         SQL
       end