Inserting data in to a table add already inserted data
<p>I have 3 tables <code>tblpermission</code>, <code>tblgroup</code>, <code>tblassigngrouppermission</code>. Then I have a design there have two comboboxes for selecting group and permission. After select I add it to a listview. Then I save it, at that time it will go to the table <code>tblassigngrouppermission</code>. </p>

<p>That table has columns such as <code>assign id</code> (default increment), <code>groupid</code>, <code>permission id</code>. All are correctly added to the table. After that saving if I select the same group for assign permission. Then I select already assigned permission and click save it added to the table. But I need there not add the already assigned permission to the table.</p>

<p>How can I do this?</p>
