单个分割（取第一个）
SELECT SUBSTRING_INDEX(name, '，',1) AS result FROM ppm_order;
全部分割
SELECT
SUBSTRING_INDEX(SUBSTRING_INDEX(name, '，', n.n), '，', -1) AS name
FROM
表
JOIN
(SELECT 1 AS n UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4) n
WHERE n.n <= LENGTH(name) - LENGTH(REPLACE(name, '，', '')) + 1;
