[localads]

Hi,

I have a table with 4 columns, one of which is an ID column. Each row has to have a unique ID, so I was thinking that I could tell PHP to find the last row in "id", and Add 1 to it, and insert this onto the next row - that way it remains unique.

But how?

Thanks,

Will

[PAV]

<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">quote:</font><HR>Originally posted by localads:
Hi,

I have a table with 4 columns, one of which is an ID column. Each row has to have a unique ID, so I was thinking that I could tell PHP to find the last row in "id", and Add 1 to it, and insert this onto the next row - that way it remains unique.

But how?

Thanks,

Will[/quote]

Hi Will,

If you work with MySQL as database, you can assign an AUTO-INCREMENT to the primary ID column. Every new inserted value will be unique and incremented by 1.

Peter

[rod k]

Also, doing this the way you've planned is dangerous. What happens if two visitors access the same script simultaneously?

[PAV]

<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">quote:</font><HR>Originally posted by rod k:
Also, doing this the way you've planned is dangerous. What happens if two visitors access the same script simultaneously?[/quote]

Well, to be sure: just catch the last inserted ID within the current connection (link) to the database: $lastID = mysql_insert_id().
But it should be no problem, because MySQL keeps track of the connections.
Otherwise, what use would it have in a multi-user environment?

Peter

[rod k]

I wasn't speaking to you PAV.