I assume that you don't want the empty group column, which is the one grouped by. If that's the case pls use "columnTops" instead of "top" in excel Table's rowGroup setting. For example:
\koolreport\excel\Table::create(array(
"dataSource" => $this->dataStore('sales'),
"columns" => [
// "customerName", // hide customerName column if you want
"productLine",
"dollar_sales" => [...]
],
"rowGroup" => [
"customerName" => [ // grouped by customerName
...
// "top" => "Top: Customers: {customerName}", // comment out "top" i.e hide the empty group column
"columnTops" => [
"productLine" => "Top: Customers: {customerName}", // show customerName group in column productLine
"dollar_sales" => "{totalSales}"
]
],
If you need something else let us know. Rgds,