mysql 去除重复字符串

Question

在标题字段中 数据是 lwm 2233, lwm 2233 怎么保留 lwm 2233数据唯一

Answer 1

示例SQL如下

SELECT distinct  substring_index(substring_index('lwm 2233,lwm 2233',',',help_topic_id + 1),',' ,- 1) AS name
FROM mysql.help_topic
WHERE help_topic_id < (length('lwm 2233,lwm 2233') - length(REPLACE ('lwm 2233,lwm 2233', ',', '')) + 1);