如何使用Javascript将特定内容从一个表复制到另一个表

Question

I am currently developing a tool to display large amount of data in different tables. Different amount of data from one table has to be assigned into another table more than once. This view takes almost 20 seconds to load and i want to lower the time by manipulating the DOM instead of assigning every match within PHP. I want to place a few identifiers hidden in the first table and on click of one row, show the additional data within the next element.

Here is an example how the Tables look before:

<table>
    <tr>
        <th>Name</th>
    </tr>
    <tr class="iWantToClickThis">
        <td>Bla Bla</td>
        <td style="visibility:hidden;">3,5</td>
    </tr>
</table>

<table style="visibility:hidden">
    <tr>
        <th>Additional Header</th>
    </tr>
    <tr id="1">
        <td>Additional Info 1</td>
    </tr>
    <tr id="2">
        <td>Additional Info 2</td>
    </tr>
    <tr id="3=>
        <td>Additional Info 3</td>
    </tr>
    <tr id="4">
        <td>Additional Info 4</td>
    </tr>
    <tr id="5">
        <td>Additional Info 5</td>
    </tr>
    <tr id="6">
        <td>Additional Info 6</td>
    </tr>
</table>

And after the click:

<table>
    <tr>
        <th>Name</th>
    </tr>
    <tr class="iWantToClickThis">
        <td>Bla Bla</td>
        <td style="visibility:hidden;">3,4,5</td>
    </tr>
    <tr>
        <td colspan="2>
            <table>
                <tr>
                    <th>Additional Header</th>
                </tr>
                <tr id="3">
                    <td>Additional Info 3</td>
                </tr>
                <tr id="5">
                    <td>Additional Info 5</td>
                </tr>
            </table>
        </td>
</table>

I've found out how to achieve this with a single row but how do i do that with different, identitying them by their ids?