[SOLVED] maths in mysql.

[daydreamer]

Hi.

 

I am trying to update a cell in my database, where I have to add the old value to a new value.

 

How do I do this in one mysql_query (instead of retrieving the number already their, adding it to the new number and updating it.).

 

This is what I have:

 

	
$member_id="22";
$newnumber="344";
$update = mysql_query("UPDATE members
                       SET number='number'+'$newnumber'
                       WHERE member_id='$member_id'");

 

Thanks.

 

 

[PFMaBiSmAd]

Single-quotes go around string values, not column names and when you put single-quotes around numeric values, mysql does more work because the number is first treated as a string, is converted to floating point (with the possible loss of percision due to the floating point conversion), and then used as a number. Try this -

 

$update = mysql_query("UPDATE members
                       SET number=number+$newnumber
                       WHERE member_id=$member_id");

[daydreamer]

works perfect - thanks for the info.