Modify HTML element of certain ID with JQuery

I am new to JQuery and I have a very basic question about this.

I have two html table elements, one with id="needColor" and another one without id.

I want to set the background color of an even row on the table with id = "needColor" but not on the table without any id.

How can I do this with the JQuery?

The current code is as follows:

<script src="http://ift.tt/1XwG72U"</script>
<script>
$(document).ready(function(){

//tried to add something like these, but I am not sure how it must be written

// this makes all the even row in "all" table to be yellow
$("tr:even").css("background-color", "yellow");

// this will give the whole yellow color of table with id = needColor
$("table[id='needColor']").css("background-color", "yellow"); // do not use ("#needColor") as this will affect other elements than "table"


});
</script>

Thanks.