MySQL Function to Calculate Murmur Hash Murmurhash (MurmurHashV2)

MurmurHashV2.sql

DROP FUNCTION IF EXISTS MurmurHashV2;
DELIMITER //
CREATE FUNCTION `MurmurHashV2`(`keyx` varchar(65535), `seed` int unsigned)
	RETURNS int unsigned
BEGIN
	DECLARE l,i,m,r INT unsigned;
	DECLARE h,k BIGINT unsigned;
	SET l = LENGTH(keyx), i=1, m =  0x5bd1e995, r=24;
	SET h = seed ^ l;
	
	
	WHILE l>=4 DO
		set k = ( ascii(mid(keyx,i,1)) & 0xff ) | 
		((ascii(mid(keyx,i+1,1)) & 0xff) << 8) |
		((ascii(mid(keyx,i+2,1)) & 0xff) << 16) |
		((ascii(mid(keyx,i+3,1)) & 0xff) << 24);
		set k = ( (k*m) & 0xffffffff );
		set k = k ^ (k >> 24);
		set k = ( (k*m) & 0xffffffff );
		set h = ( (h*m) & 0xffffffff );
		set h = h^k;
		set l = l-4;
		set i = i+4;
	END WHILE;
	IF l>=3  THEN SET h = h^((ascii(mid(keyx,i + 2,1)) & 0xff) << 16); END IF;
	IF l>=2 THEN SET h = h^((ascii(mid(keyx,i + 1,1)) & 0xff) << 8); END IF;
	IF l>=1 THEN SET h = h^(ascii(mid(keyx,i,1)) & 0xff);
			set h = ( (h*m) & 0xffffffff );
	END IF;
	Set h = h^(h >> 13);
   set h = ( (h*m) & 0xffffffff );
   set h = h^(h >> 15);
	RETURN h;  -- AUTO CAST
END;//
DELIMITER ;

Select MurmurHashV2('test', 0);