在php上删除数据后无法创建新记录

Question

im newbie here, i have a trouble like this.

table: nota

no_nota(pk) name addres

D01 xxx xxxx

D02 xxx xxxx

D03 xxx xxxx

when im delete no_nota "D02" then i want to make new record, no_nota should be D04. but in my case no_nota be D03 not D04. my syntax code like this.

<td>No Nota : </td> <td><?php $sql=mysql_query("SELECT * FROM nota"); $data=(mysql_num_rows($sql)+1); ?> <input type="text" value="<?php echo "$data"; ?>" name="no_nota" required/><b></b> </td>

someone how can tell me the right syntax? sory for my bad english regards,

Answer 1

It seems you don't need to store your no_nota at all. Using an auto-increment from the database, you will always have the correct number and you can build your no_nota on the fly.

After inserting in the database of course. Technically you could query for the next auto-increment number but that will get you into a race condition if multiple users are using the system at the same time.