Chart display issue for some queries

[madalincm]

Issue Summary:

Build identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0
Window 7 64 Bit

Steps to Reproduce:

1. Open the following query: https://sql.telemetry.mozilla.org/queries/2054#3731
2. Hover over the chart and observe the value displayed for the 3rd and the 4th bars

Expected results:

The size of the bar is proportional with its value.

Actual results:

The bar having a value of 14.301k is having the same size as the one with value of 1.

Notes/Issues:

Verified in FF52(Win7). Issue can be reproduced in STMO-production.
Screencast for this issue:

[alison985]

Here's a fork showing the chart if they did a groupby and stacked it: https://sql.telemetry.mozilla.org/queries/4880/source#9978

The issue here is there are 3 column and it seems to be auto-grouping by the x-axis field and not recognizing the version distinction by default.

[alison985]

On my local test case, it should look like:

but when I remove the groupby column it looks like this:

Notice that the "query" column is shorter in the second picture, because unlike the production test case it is only grabbing 1 of the multiple values for query in the underlying table instead of grouping them. However, this is also an error because it falsely misrepresents the action_count of "query" as too low by discarding records.

There are a couple of paths to resolution as I see it:

1. a) allow for multiple columns to be selected into the X axis form field so distinctions are made and more columns show up on the graph to represent all result rows and b) if there are more than 2 dimensions in a query auto-add the non-used dimensions to an "ignore column" form field/configuration value.
2. Default stacking to enabled so people have to opt-out of seeing the distinctions should this case occur. (User error prone.)
3. Start showing the user warnings on graph configurations that don't make sense. For instance: related to Display issue for long info displayed on the x-axis of a chart #58 {pseudocode} if x-axis label height > 50 then show warning to edit x-axis height field {/pseudocode}, related to this ticket: {pseudocode} if 2 or more dimensions then show warning to alter query to 2 columns or add group by and enable stacking {/pseudocode}
4. Figure out a way to stop the x-axis labels from being limited to occurring in the list of values only once.
5. something else I haven't thought of yet

The argument for option #3 in my opinion is:
i) Teaches users more about the chart edit options available to them as a side effect while correcting for the issue.
ii) The code should be much easier/faster to write because it's "detect this and display a warning" as opposed to "find this case and handle it and its related cases gracefully". Also reduces the possibility of finding future unaccounted for edge case bugs.
iii) Sets a foundation for giving additional warnings and best practice information on charts to users in the future. (i.e. "You probably really don't want a pie chart.", etc.)

[alison985]

Error and warnings for this ticket implemented in PR #91. I left the issue from #58 alone because it's way harder.