1 files changed, 20 insertions, 0 deletions
diff --git a/challenge-142/luca-ferrari/postgresql/ch-1.sql b/challenge-142/luca-ferrari/postgresql/ch-1.sql
new file mode 100644
index 0000000000..57de950651
--- /dev/null
+++ b/challenge-142/luca-ferrari/postgresql/ch-1.sql
@@ -0,0 +1,20 @@
+CREATE OR REPLACE FUNCTION
+  f_divisors_last_digit( m int, n int )
+  RETURNS SETOF int
+AS $CODE$
+  WITH RECURSIVE numbers AS (
+    SELECT 1 as num
+     UNION
+    SELECT num + 1
+      FROM numbers
+     WHERE num + 1 <= m )
+  , divisors AS (
+    SELECT num as div
+      FROM numbers
+      WHERE m % num = 0 )
+  SELECT count(*)
+  FROM divisors
+  WHERE div::text LIKE ( '%' || n::text );
+
+  $CODE$
+  LANGUAGE sql;