1 files changed, 13 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb b/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
index 84354c0187..740832d6b8 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/quoting.rb
@@ -40,13 +40,22 @@ module ActiveRecord
           COLUMN_NAME_WITH_ORDER
         end
 
-        COLUMN_NAME = /\A(?:(`?)\w+\k<1>\.)?(`?)\w+\k<2>\z/i
+        COLUMN_NAME = /
+          \A
+          (
+            (?:\w+\.|`\w+`\.)?(?:\w+|`\w+`)
+          )
+          (?:\s*,\s*\g<1>)*
+          \z
+        /ix
 
         COLUMN_NAME_WITH_ORDER = /
           \A
-          (?:(`?)\w+\k<1>\.)?
-          (`?)\w+\k<2>
-          (?:\s+ASC|\s+DESC)?
+          (
+            (?:\w+\.|`\w+`\.)?(?:\w+|`\w+`)
+            (?:\s+ASC|\s+DESC)?
+          )
+          (?:\s*,\s*\g<1>)*
           \z
         /ix