$tmp_insert_sql="insert into user(name) values('".$name."')";
$query_insert=mysql_query($tmp_insert_sql,$db);$tmp_update_sql="update user set name='xxx' where name='".$name."'";
$query_update=mysql_query($tmp_update_sql,$db);$tmp_delete_sql="delete from user where name='".$name."'";
$query_delete=mysql_query($tmp_delete_sql,$db);
//select
$sqltxt="select* from user where name='".$name."'"; //insert user
$sqltxt="insert into user (字段1,字段2) values (字段1值,字段2值) where name='".$name."'";
//update
$sqltxt="update user set 字段=值 where name='".$name."'";
//delete
$sqltxt="delete from user where name='".$name."'"; 字段值一般加引号