replace用法：replace（"欄位名","原字串","替代後的字串"）

用法示例：替換expand_url中https為http

原資料：

為了識別率更高加上冒號

update jianjie_task_list_tg set expand_url = replace(expand_url,'https:','http:');

執行後資料：

也可以加條件：

update jianjie_task_list_tg set expand_url = replace(expand_url,'http:','https:') where id =6;
 

update jianjie_task_list_tg set expand_url = replace(expand_url,'/test1.jiujijianghu.com/','/www.baidu.com/') where id =6;