zxcvbnmluton的专栏

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was43810 seconds ago.The last packet sent successfully to the server was 43810 seconds a

update a set B=replace（B,'3','') where b like '%3%'用replace其中三个参数replace(原字符串，要替换的字符，替换成的字符) 哦 后面的条件多余，可以直接：update a set B=replace（B,'3','')