一个字符串-279-263-196-054-044-068-062-130-149以分割获取最大值用mysql 写代码

SELECT MAX(CAST(value AS DECIMAL(10,2))) FROM (SELECT SUBSTRING_INDEX(SUBSTRING_INDEX(''-2.79,-2.63,-1.96,-0.54,-0.44,-0.68,-0.62,-1.30,-1.49''', ',', numbers.n), ',', -1) AS value FROM (SELECT @row := @row + 1 AS n FROM (SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) t1, (SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) t2, (SELECT @row := 0) t3) numbers WHERE CHAR_LENGTH(''-2.79,-2.63,-1.96,-0.54,-0.44,-0.68,-0.62,-1.30,-1.49''') - CHAR_LENGTH(REPLACE(''-2.79,-2.63,-1.96,-0.54,-0.44,-0.68,-0.62,-1.30,-1.49''', ',', '')) >= numbers.n - 1) t;