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@vadviktor
Created March 11, 2014 14:40
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Legacy MySQL (v 5.1) BASE64 functions
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for base64_data
-- ----------------------------
DROP TABLE IF EXISTS `base64_data`;
CREATE TABLE `base64_data` (
`c` char(1) CHARACTER SET utf8 COLLATE utf8_bin DEFAULT NULL,
`val` tinyint(4) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of base64_data
-- ----------------------------
INSERT INTO `base64_data` VALUES ('A', '0');
INSERT INTO `base64_data` VALUES ('B', '1');
INSERT INTO `base64_data` VALUES ('C', '2');
INSERT INTO `base64_data` VALUES ('D', '3');
INSERT INTO `base64_data` VALUES ('E', '4');
INSERT INTO `base64_data` VALUES ('F', '5');
INSERT INTO `base64_data` VALUES ('G', '6');
INSERT INTO `base64_data` VALUES ('H', '7');
INSERT INTO `base64_data` VALUES ('I', '8');
INSERT INTO `base64_data` VALUES ('J', '9');
INSERT INTO `base64_data` VALUES ('K', '10');
INSERT INTO `base64_data` VALUES ('L', '11');
INSERT INTO `base64_data` VALUES ('M', '12');
INSERT INTO `base64_data` VALUES ('N', '13');
INSERT INTO `base64_data` VALUES ('O', '14');
INSERT INTO `base64_data` VALUES ('P', '15');
INSERT INTO `base64_data` VALUES ('Q', '16');
INSERT INTO `base64_data` VALUES ('R', '17');
INSERT INTO `base64_data` VALUES ('S', '18');
INSERT INTO `base64_data` VALUES ('T', '19');
INSERT INTO `base64_data` VALUES ('U', '20');
INSERT INTO `base64_data` VALUES ('V', '21');
INSERT INTO `base64_data` VALUES ('W', '22');
INSERT INTO `base64_data` VALUES ('X', '23');
INSERT INTO `base64_data` VALUES ('Y', '24');
INSERT INTO `base64_data` VALUES ('Z', '25');
INSERT INTO `base64_data` VALUES ('a', '26');
INSERT INTO `base64_data` VALUES ('b', '27');
INSERT INTO `base64_data` VALUES ('c', '28');
INSERT INTO `base64_data` VALUES ('d', '29');
INSERT INTO `base64_data` VALUES ('e', '30');
INSERT INTO `base64_data` VALUES ('f', '31');
INSERT INTO `base64_data` VALUES ('g', '32');
INSERT INTO `base64_data` VALUES ('h', '33');
INSERT INTO `base64_data` VALUES ('i', '34');
INSERT INTO `base64_data` VALUES ('j', '35');
INSERT INTO `base64_data` VALUES ('k', '36');
INSERT INTO `base64_data` VALUES ('l', '37');
INSERT INTO `base64_data` VALUES ('m', '38');
INSERT INTO `base64_data` VALUES ('n', '39');
INSERT INTO `base64_data` VALUES ('o', '40');
INSERT INTO `base64_data` VALUES ('p', '41');
INSERT INTO `base64_data` VALUES ('q', '42');
INSERT INTO `base64_data` VALUES ('r', '43');
INSERT INTO `base64_data` VALUES ('s', '44');
INSERT INTO `base64_data` VALUES ('t', '45');
INSERT INTO `base64_data` VALUES ('u', '46');
INSERT INTO `base64_data` VALUES ('v', '47');
INSERT INTO `base64_data` VALUES ('w', '48');
INSERT INTO `base64_data` VALUES ('x', '49');
INSERT INTO `base64_data` VALUES ('y', '50');
INSERT INTO `base64_data` VALUES ('z', '51');
INSERT INTO `base64_data` VALUES ('0', '52');
INSERT INTO `base64_data` VALUES ('1', '53');
INSERT INTO `base64_data` VALUES ('2', '54');
INSERT INTO `base64_data` VALUES ('3', '55');
INSERT INTO `base64_data` VALUES ('4', '56');
INSERT INTO `base64_data` VALUES ('5', '57');
INSERT INTO `base64_data` VALUES ('6', '58');
INSERT INTO `base64_data` VALUES ('7', '59');
INSERT INTO `base64_data` VALUES ('8', '60');
INSERT INTO `base64_data` VALUES ('9', '61');
INSERT INTO `base64_data` VALUES ('+', '62');
INSERT INTO `base64_data` VALUES ('/', '63');
INSERT INTO `base64_data` VALUES ('=', '0');
-- ----------------------------
-- Function structure for BASE64_DECODE
-- ----------------------------
DROP FUNCTION IF EXISTS `BASE64_DECODE`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` FUNCTION `BASE64_DECODE`(input BLOB) RETURNS blob
DETERMINISTIC
SQL SECURITY INVOKER
BEGIN
DECLARE ret BLOB DEFAULT '';
DECLARE done TINYINT DEFAULT 0;
IF input IS NULL THEN
RETURN NULL;
END IF;
each_block:
WHILE NOT done DO BEGIN
DECLARE accum_value BIGINT UNSIGNED DEFAULT 0;
DECLARE in_count TINYINT DEFAULT 0;
DECLARE out_count TINYINT DEFAULT 3;
each_input_char:
WHILE in_count < 4 DO BEGIN
DECLARE first_char CHAR(1);
IF LENGTH(input) = 0 THEN
RETURN ret;
END IF;
SET first_char = SUBSTRING(input,1,1);
SET input = SUBSTRING(input,2);
BEGIN
DECLARE tempval TINYINT UNSIGNED;
DECLARE error TINYINT DEFAULT 0;
DECLARE base64_getval CURSOR FOR SELECT val FROM base64_data WHERE c = first_char;
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET error = 1;
OPEN base64_getval;
FETCH base64_getval INTO tempval;
CLOSE base64_getval;
IF error THEN
ITERATE each_input_char;
END IF;
SET accum_value = (accum_value << 6) + tempval;
END;
SET in_count = in_count + 1;
IF first_char = '=' THEN
SET done = 1;
SET out_count = out_count - 1;
END IF;
END; END WHILE;
-- We've now accumulated 24 bits; deaccumulate into bytes
-- We have to work from the left, so use the third byte position and shift left
WHILE out_count > 0 DO BEGIN
SET ret = CONCAT(ret,CHAR((accum_value & 0xff0000) >> 16));
SET out_count = out_count - 1;
SET accum_value = (accum_value << 8) & 0xffffff;
END; END WHILE;
END; END WHILE;
RETURN ret;
END
;;
DELIMITER ;
-- ----------------------------
-- Function structure for BASE64_ENCODE
-- ----------------------------
DROP FUNCTION IF EXISTS `BASE64_ENCODE`;
DELIMITER ;;
CREATE DEFINER=`YOUR DATABASE`@`%` FUNCTION `BASE64_ENCODE`(input BLOB) RETURNS blob
DETERMINISTIC
SQL SECURITY INVOKER
BEGIN
DECLARE ret BLOB DEFAULT '';
DECLARE done TINYINT DEFAULT 0;
IF input IS NULL THEN
RETURN NULL;
END IF;
each_block:
WHILE NOT done DO BEGIN
DECLARE accum_value BIGINT UNSIGNED DEFAULT 0;
DECLARE in_count TINYINT DEFAULT 0;
DECLARE out_count TINYINT;
each_input_char:
WHILE in_count < 3 DO BEGIN
DECLARE first_char BLOB(1);
IF LENGTH(input) = 0 THEN
SET done = 1;
SET accum_value = accum_value << (8 * (3 - in_count));
LEAVE each_input_char;
END IF;
SET first_char = SUBSTRING(input,1,1);
SET input = SUBSTRING(input,2);
SET accum_value = (accum_value << 8) + ASCII(first_char);
SET in_count = in_count + 1;
END; END WHILE;
-- We've now accumulated 24 bits; deaccumulate into base64 characters
-- We have to work from the left, so use the third byte position and shift left
CASE
WHEN in_count = 3 THEN SET out_count = 4;
WHEN in_count = 2 THEN SET out_count = 3;
WHEN in_count = 1 THEN SET out_count = 2;
ELSE RETURN ret;
END CASE;
WHILE out_count > 0 DO BEGIN
BEGIN
DECLARE out_char CHAR(1);
DECLARE base64_getval CURSOR FOR SELECT c FROM core_base64_data WHERE val = (accum_value >> 18);
OPEN base64_getval;
FETCH base64_getval INTO out_char;
CLOSE base64_getval;
SET ret = CONCAT(ret,out_char);
SET out_count = out_count - 1;
SET accum_value = accum_value << 6 & 0xffffff;
END;
END; END WHILE;
CASE
WHEN in_count = 2 THEN SET ret = CONCAT(ret,'=');
WHEN in_count = 1 THEN SET ret = CONCAT(ret,'==');
ELSE BEGIN END;
END CASE;
END; END WHILE;
RETURN ret;
END
;;
DELIMITER ;
@maslbl4
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maslbl4 commented Dec 8, 2015

Error in line 203. Wrong table name 'core_base64_data' must be 'base64_data'

@sgulbetekin
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nice one, saved us a lot of work! 👍

@nigamnishant
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Nice one, works like charm, but having issues while decoding special characters like ö, ørn Eidsvåg. Any idea on how to resolve this and update the decode function to support the same.
Any help or assistance would be appreciated.

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