1 files changed, 27 insertions, 0 deletions
diff --git a/challenge-261/luca-ferrari/plpgsql/ch-1.sql b/challenge-261/luca-ferrari/plpgsql/ch-1.sql
new file mode 100644
index 0000000000..d12067ac9a
--- /dev/null
+++ b/challenge-261/luca-ferrari/plpgsql/ch-1.sql
@@ -0,0 +1,27 @@
+--
+-- Perl Weekly Challenge 261
+-- Task 1
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-261>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc261;
+
+CREATE OR REPLACE FUNCTION
+pwc261.task1_plpgsql( nums int[] )
+RETURNS int
+AS $CODE$
+
+WITH sum_numbers AS ( SELECT SUM( n::int ) AS y FROM unnest( nums ) n )
+     , digits AS ( SELECT regexp_split_to_table( n::text, '' ) d
+       	      	   FROM unnest( nums ) n )
+      , sum_digits AS ( SELECT SUM( d::int ) AS x FROM digits d )
+     , result AS ( SELECT y - x AS r
+                   FROM sum_numbers, sum_digits )
+
+     SELECT CASE WHEN r > 0 THEN r
+            ELSE r * -1
+	    END
+
+    FROM result;
+$CODE$
+LANGUAGE sql;