[RESOLVED] Reducing figures in a specific column

DangerM0use

I have a lot of figures in a column in a table, and we have found out they are all wrong - an extra 3% was put onto those figures. Because there are so many rows of figures in this coulmn (Well over a thousand) we need a quick way to do this.
How can you edit column "figures" so that the figures are reduced by 3%? They don't need to be displayed - that is done later on in the code and that is all OK. I just need to edit the figures right now.
Cheers.

NogDog

Are you talking about a database column or a HTML table column? If the former, a fairly simple update query could make the change. If the latter, we'll need to see what the text data looks like that you want to change. You might be able to use preg_replace() with the "e" modifier or preg_replace_callback() to do it.

bradgrafelman

For an example of how to reduce an entire column of data by 3%, a query such as this should work:

UPDATE myTable SET col1 = (col1 * .97)

DangerM0use

Hi, sorry didn't get a chance to post but I managed tofigure it out last night, but thanks for the suggestions and brad - that is how I did it. Thanks again!

NogDog

Note that if the original values were multiplied by 1.03 and then you multiplied the results by .97, you've lost about a tenth of a percent on each value. For example:

$start = 10.00;
$plus3pct = $start * 1.03;
$minus3pct = $plus3pct * .97;
printf('%.3f -> %.3f -> %.3f', $start, $plus3pct, $minus3pct);

Output:

10.000 -> 10.300 -> 9.991