Trouble adding and removing elements in d3 - d3.js

Question

My goal is to remove a data point from my bar chart.
It will then update itself:
Update X and Y axis
Update the actual bar chart
Update the legend
Issues I am having:
When I exit().remove() the rectangles in my graph, the code also gets rid of the rectangles in the legend. When I try to enter() the rectangles in my legend, they do not appear. I am not sure what is happening here, but I am not being successful in adding and removing elements due to data changes. Any help would be appreciated.
Code snippet of where I think I am having issues:
This is the part that also deletes the rectangles in the legend (I am not sure if I should do this here or in the enter/update/delete part of the legend)
The code below is executed right after the user clicks the "delete all" button. My intent here is to only delete one bar (the one named "ALL") and update the chart.
//Select rectangles
var bars = svg.selectAll("rect")
.data(dataset, function(d) { return d.State; });
//Enter rectangles
bars.enter()
.append("rect")
.style("fill", function(d,i) { return color(i) })
.attr("x", function(d) { return xScale(d.State); })
.attr("y", function(d) { return yScale(d.CustomerCount) })
.attr("width", xScale.rangeBand()) //returns rangeRoundBands width
.attr("height", function(d) { return h - yScale(d.CustomerCount) });
//Update rectangles
bars.transition()
.duration(1000)
.style("fill", function(d,i) { return color(i) })
.attr("x", function(d) { return xScale(d.State); })
.attr("y", function(d) { return yScale(d.CustomerCount) })
.attr("width", xScale.rangeBand()) //returns rangeRoundBands width
.attr("height", function(d) { return h - yScale(d.CustomerCount) });
//Exit rectangles
bars.exit()
.transition()
.duration(500)
.attr("x", w)
.remove();
Here is entire the code:
http://plnkr.co/edit/Nue5bocQsI4E6D5wfNSP
Here is the slightly smaller code:
I tried to reduce the code as much as possible but it is still pretty big.
http://jsfiddle.net/aNQWV/

Answer 1

In the part where you update the data you say:
var bars = svg.selectAll("rect")
.data(dataset, function(d) { return d.State; });
The problem is that at this point the svg contains two kind of rects. One kind corresponds to the bars, and the other ones are part of the legend. This means that you are joining the new data to this mix of rects, while actually you wanted to join the new data with the bars only.
So, you need a more specific selector that targets only the bar rects. The typical approach is to add a class to those rects when you create them:
svg.selectAll(".bar")
.data(input)
.enter().append("rect")
.attr("class", "bar");
Then in the part where you update the data you would say:
var bars = svg.selectAll(".bar")
.data(dataset, function(d) { return d.State; });