modify sql functions

sql/create_tables.sql

@@ -1,20 +1,22 @@
-CREATE OR REPLACE PROCEDURE create_tables() AS $$
+CREATE OR REPLACE PROCEDURE public.create_tables() 
+LANGUAGE SQL
+AS $$
 	DROP TABLE IF EXISTS artist_website;
 	DROP TABLE IF EXISTS website;
 	DROP TABLE IF EXISTS artist;
-
+	
 	CREATE TABLE IF NOT EXISTS artist (
 		id serial PRIMARY KEY,
 		name text NOT NULL,
 		CONSTRAINT a_name UNIQUE(name)
 	);
-
+	
 	CREATE TABLE IF NOT EXISTS website (
 		id serial PRIMARY KEY,
 		name text NOT NULL,
 		CONSTRAINT w_name UNIQUE(name)
 	);
-
+	
 	CREATE TABLE IF NOT EXISTS artist_website (
 		id serial PRIMARY KEY,
 		url text NOT NULL,
@@ -26,4 +28,4 @@ CREATE OR REPLACE PROCEDURE create_tables() AS $$
 		CONSTRAINT aw_artist FOREIGN KEY (artist_id) REFERENCES artist (ID),
 		CONSTRAINT aw_website FOREIGN KEY (website_id) REFERENCES website (ID)
 	);
-$$ LANGUAGE SQL;
+$$;