using (SPSite siteCol = new SPSite("http://mySharepoint/"))
{
    using (SPWeb web = siteCol.RootWeb)
    {
        SPList list = web.GetList("/Lists/PermissionMatrix");

        SPListItem item = list.GetItemByIdSelectedFields([*Requires ID*], "Role");

        String role1= (String)item["Roles"];
    }
}
	
var sampleQuery = new SPQuery();
sampleQuery.Query = @"<Where>
     <And>
       <FieldRef Name='Status' />
       <Value Type='Text'>Completed</Value>
     </And>
     <Gt>
       <FieldRef Name='Id' />
       <Value Type='Number'>20</Value>
     </Gt>
   </Where>";
var foundItems = list.GetItems(sampleQuery);