I would not advise going in and just running a query. Not only were the tests added to the coverage but the test configurations are also linked now. This workflow below will allow you to create an icon on the requirements tool bar that will allow you to removed the coverage for both the tests and test configurations.
The first step is to create a button in the Requirements Module Customize --> Workflow --> Script Editor --> Toolbar Button Editor
- select Requirements in the Command bar drop-down
- click the Add button
- enter a Hint if needed and Select an icon image
- click Apply
*** Make a note of the action name in this case it is Requirements_Action1 you will need to update it in the workflow below if it is different ***
Finally, add the following under Customize --> Workflow --> Script Editor --> Common script --> ActionCanExecute(ActionName)
      If ActionName = ''Requirements_Action1'' then
         Ans = msgbox(''You are about to remove a requirement coverage for all tests!'' & vbCrLf & ''Are you sure you want to do this?'', vbYesNo + vbExclamation + vbDefaultButton2, ''Warning'')
         If Ans = vbYes Then
            Dim thisTestList 'Holds list of tests covering this requirement
            Dim aTest 'The test from thisTestList that the requirement is being removed from
            Dim thisReqFact 'Services for managing requirements
            Dim thisReqFilter 'The TDFilter object for the requirement factory
            Dim thisReqList 'List of object according to specified filter ()
            Dim aReq 'The current requirement from the thisReqList
            Dim thisReqID 'Holds the requirement ID for the TDFilter
            thisReqID = InputBox(''Enter the Requirement ID to remove coverage'', ''Requirement ID'') 'Prompts user for requirement ID to use in filter
            Do while thisReqID = '''' Or NULL
                  thisReqID = InputBox(''You did not enter a requirement ID!'' & vbCrLf & ''Enter the Requirement ID to remove coverage'', ''Requirement ID'')
            Loop
            set tdc = TDConnection
            set thisReqFact = tdc.ReqFactory 'Creates the requirement factory
            set thisReqFilter = thisReqFact.Filter 'Creates the TDFilter for creating the list of requirements
            thisReqFilter.Filter(''RQ_REQ_ID'') = '''' & thisReqID & '''' 'Sets the Filter used (the '''' at the beginning and end forces the variable to be evaluated as a string)
            set thisReqList =  thisReqFact.NewList(thisReqFilter.Text) 'Creates the filtered list of requirements
            For Each aReq in thisReqList 'Loops throught the list of requirements one at a time
               set thisTestList = aReq.GetCoverList() 'Gets the list of tests covering this requirement
               msgbox ''There are '' & thisTestList.Count & '' test covering the requirement'' 'displays the number of tests covering the requirement
               For Each aTest in thisTestList 'Loops the lists of tests
                  aTest.RemoveCoverage(aReq) 'removes the coverage
               Next
            Next
         End If
      End If
***Directions:***
When you click on the icon image that was added to the requirements tool bar you will be prompted whether or not you want to remove the coverage for all tests for the requirement. Next you will be prompted for the requirement ID. A message box telling the number of covering tests will display (click OK). The covering tests and test configurations will be removed.