怎么替换mysql数据库中A字段中符号

update table set A = replace(A,'\\,.','你要替换的值') where ...

update table set A = replace(A,'\\','')

update table set A = replace(A,'\\','')

$sql = "update table set A = replace(A,'\\\\','')";

$sqlstr = "update b set url=replace(url,'\\\\','')";
mysql_query($sqlstr) or die(mysql_error());