CSV Export – Fix Displaced Rows and Excessive Rows Issue

Create a separate block definition - e.g. duplicate the Grid block to another block that's specific for your CSV; I would call this Csvgrid.php instead of Grid.php - it would contain all of the same functionality that the normal Grid.php contains, but omit the one column.

In your controller:

public function exportCsvAction()
{
        $fileName = 'myreport_'.date('Y_m_d_h_i_s').'.csv';
        $content = $this->getLayout()->createBlock('mymodule/adminhtml_reports_csvgrid')->getCsv();
}

When duplicating the Grid, place Csvgrid.php into the same physical directory as Grid.php but rename it accordingly - don't forget to change the class name!

Edit:

So it turns out that Mage_Adminhtml_Block_Widget_Grid has a method called removeColumn - defined as:

/

**
     * Remove existing column
     *
     * @param string $columnId
     * @return Mage_Adminhtml_Block_Widget_Grid
     */
    public function removeColumn($columnId)
    {
        if (isset($this->_columns[$columnId])) {
            unset($this->_columns[$columnId]);
            if ($this->_lastColumnId == $columnId) {
                $this->_lastColumnId = key($this->_columns);
            }
        }
        return $this;
    }

My guess is that because Mage_Adminhtml_Block_Report_Grid extends Mage_Adminhtml_Block_Widget_Grid it inherits this method and should be able to be used. I would, in that case, create a new block Grid and extend the Grid that your current report is in. From there you can use your own prepareColumns method, call the parent::_prepareColumns() and then call removeColumn..

Best of luck.

The file you generated through Magento Export (whether this is default import/export module or default dataflow profile) is NOT going to work if you import it back, because it doesn't preserve the format.

If you want to update weights, I would recommend this:
1) filter your CSV in Excel, filter only those which have "sku" field assigned
2) copy-paste the filtered rows into new spreadsheet
3) leave only 2 columns - "sku", "weight"
4) import it back.

I'm pretty sure it's the easiest flow to solve your concrete task.

For those who are looking for tool for Magento that allows both export and import while having similar format for both routines, check out this one.