Create very basic hello world PL/pgSQL function

SQL/plpgsql/call_hello.sql

@@ -0,0 +1 @@
+SELECT hello();

SQL/plpgsql/create_hello.sql

@@ -0,0 +1,12 @@
+CREATE OR REPLACE FUNCTION hello() RETURNS varchar AS $$
+<< outerblock >>
+DECLARE
+    greetings varchar := 'Hello PL/pgSQL !';
+BEGIN
+    RAISE NOTICE 'From hello() : %', greetings;
+    greetings := 'Bye !';
+    RAISE NOTICE 'From hello() : %', greetings;
+
+    RETURN greetings;
+END;
+$$ LANGUAGE plpgsql;