Add Italian video course about SQL (#3403)

free-courses-it.md

@@ -7,6 +7,7 @@
 * [C Sharp](#c-sharp)
 * [C++](#c++)
 * [Database](#database)
+  * [SQL](#sql)
 * [Delphi](#delphi)
 * [Embedded](#embedded)
   * [Arduino](#arduino)
@@ -70,6 +71,11 @@
 * [Basi di Dati](https://www.youtube.com/playlist?list=PLAQopGWlIcyZ7CN1sefdnCusfoodLP931) (T. Catarci)
 
 
+#### SQL
+
+* [Corso SQL](https://www.youtube.com/playlist?list=PLE555DB6188C967AC) (F. Camuso)
+
+
 ### Delphi
 
 * [Videocorso Delphi/Lazarus](https://www.youtube.com/watch?v=JxE1nUqriV0&list=PLF75FB30719A09FA2) (F. Camuso)