Finding the next number

Hi,

When i add a new entry into my table i want to check all previous rows in the field row_order to check what is the highest numbers. Then i want to add 1 to this number and use it for the current entry in the row_order field.

How would i do this?

Cheers,
Adam

 

why not just have a column that has the auto-increment on it? This makes the new row with the next highest number

 

Why don't you just set the row_order field to auto_increment?

 

Its because the column values will be changed by the user.

 

make row_order auto_increment

edit: if for whatever reason you don't want to do that, you could always get the highest number like this:

SELECT row_order FROM table ORDER BY row_order DESC LIMIT 1

 

There may be a short-cut that I don't know of, but I guess you'll need to query the database to get the value that you're looking for (select row_order from tablename order by row_order desc limit 1), save that off and re-query the db to insert the new row, adding 1 to the result of the previous query for row_order.

Is this what you're trying to do, or am I missing something?

 

Right it is working now thanks

 

Why are you doing it like this, though? That seems pretty... inefficient

 

why are you making confussion brothers. just use MAX(id)

like

$max = max id
$next = $max + 1

max id should be taken from db using MAX(id) ... thanks