Exporting upto date grid line to excel while making line update on each call

For a form data i need to export it to an excel file through datagrid export botton. A single line represents the scores assinged by different teahers. As each teacher assigns the score one by one so for one complete result i am getting multiple lines i.e. one line for each scoring from teacher. I want to have a single line show scores given by each teach. as follows. The work is as follows, The Macth teacher will login and submitt his given scores then grid have one single line. When Physisc teacher will login he will ener his data and on this stage his data should be added next to previously added line. and same for chemistry teacher. On each submission the line will be modified the old lines will be deleted and only a single updated line will be saved. At the end I should have a single result line. How I can get it?
1 answers

You can do this with entity access. If you create for each class. So Math role, Chemistry etc. In the entity access give write rights to the score of that class and read rights to all the other attributes. This way when editing the object the math teacher with the role Math can only edit the math score while the chemistry teacher can only edit the Chemistry score while all are working on the same record.