Adding 2 columns with SUM instead of CONCAT

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First off, let me just say, that this is really amazing code. I have only been 
using php/mysql and javascript for less than a year, and setting up your grid 
was very easy, and the final product looks great.  

I would like users to set different variables to interact with the table, i.e 
changing the cost of a widget would update the grid with new profit. 
Is there a way to have a column that shows the sum of 2 other columns, or show 
1 column value times a variable?

Original issue reported on code.google.com by david...@gmail.com on 23 Aug 2012 at 3:23

[GoogleCodeExporter]

I figured it out, just had to add single quotes around the php var

$grid->fields = array(
        "gross_preship"=>"CONCAT(`ship_cost` + `ship_cost_win` +'$var_test')",
        "gross_profit"=>"CONCAT('$gross_preship' + `ship_cost_win` +'$var_test')",
                );

Original comment by david...@gmail.com on 23 Aug 2012 at 5:56