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diff --git a/challenge-256/luca-ferrari/plpgsql/ch-2.sql b/challenge-256/luca-ferrari/plpgsql/ch-2.sql
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+--
+-- Perl Weekly Challenge 256
+-- Task 2
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-256>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc256;
+
+CREATE OR REPLACE FUNCTION
+pwc256.task2_plpgsql( lw text, rw text )
+RETURNS text
+AS $CODE$
+DECLARE
+	max_index int;
+	output text := '';
+	next_char char;
+BEGIN
+	CREATE TEMPORARY TABLE IF NOT EXISTS words( l char, r char, o int );
+	TRUNCATE words;
+
+	INSERT INTO words( l, o )
+	SELECT v, row_number() over ()
+	FROM regexp_split_to_table( lw, '' ) v;
+
+	INSERT INTO words( r, o )
+	SELECT v, row_number() over ()
+	FROM regexp_split_to_table( rw, '' ) v;
+
+	SELECT max( o )
+	INTO max_index
+	FROM words;
+
+	FOR i IN 1 .. max_index LOOP
+	    SELECT l
+	    INTO next_char
+	    FROM words
+	    WHERE o = i
+	    AND l IS NOT NULL;
+
+	    IF FOUND AND next_char IS NOT NULL THEN
+	       output := output || next_char;
+	    END IF;
+
+	    SELECT r
+	    INTO next_char
+	    FROM words
+	    WHERE o = i
+	    AND r IS NOT NULL;
+
+	    IF FOUND AND next_char IS NOT NULL THEN
+	       output := output || next_char;
+	    END IF;
+	END LOOP;
+
+	RETURN output;
+
+END
+$CODE$
+LANGUAGE plpgsql;