diff --git a/HowtoMySQL.md b/HowtoMySQL.md
index 9eb0632b..70241f18 100644
--- a/HowtoMySQL.md
+++ b/HowtoMySQL.md
@@ -805,6 +805,13 @@ order by index_schema,
          index_name;
 ~~~
 
+Lister la taille des tables, des indexs, et l'espace libre (vide) de chaques tables :
+
+~~~
+select  ENGINE, TABLE_NAME,Round( DATA_LENGTH/1024/1024) as data_length , round(INDEX_LENGTH/1024/1024) as index_length, round(DATA_FREE/ 1024/1024) as data_free from information_schema.tables  where  DATA_FREE > 0;
+~~~
+
+
 ## Logs
 
 ### Log de toutes les requêtes