fix: row limits & row count labels are confusing

[mistercrunch]

SUMMARY

Currently, in explore & dashboard, we usually apply a row limit
on the query we issue against the database.

Following this, some visualization backend code does some
post-processing on data frames using pandas, typically pivoting
some things, which affects the result set's row count in
intricate capacities.

Now from a UX standpoint the user is exposed with:

• row limits in the control panels
• row count in various areas of the UI where visualization, preview,
  samples and raw results are shown

Currently we show the rowcount that's from row-processing. So maybe
a hard limit was applied at 1000 rows on the database, but we
pivot and it goes does to say 532, and we show the user that
we haven't hit the limit when we actually did.

Also note that the component that shows rowcount is supposed
to turn red if limit is hit, letting the user know they are looking at
truncated data.

This PR carries the right row count to the RowCountLabel above the visualization in explore so that it can turn red if the limit is reached reliably.

For now, this PR does not do anything new around the other RowCountLabel located in the RESULTS (south) pane. This area show the post-processed rows from cache, and seem like is has to show its matching post-processed row count. Note that the row count here is not guaranteed to match the one above.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

Passing the actual row count returned from the database and using it to surface the [improved] tooltip

TESTING INSTRUCTIONS

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 69.82%. Comparing base (5b1d6b2) to head (e5de7e1).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #27700      +/-   ##
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+ Coverage   67.38%   69.82%   +2.43%     
==========================================
  Files        1920     1920              
  Lines       75242    75247       +5     
  Branches     8423     8423              
==========================================
+ Hits        50705    52544    +1839     
+ Misses      22476    20642    -1834     
  Partials     2061     2061              

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javascript	57.40% <100.00%> (-0.02%)	⬇️
mysql	77.88% <100.00%> (?)
postgres	78.00% <100.00%> (+<0.01%)	⬆️
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python	83.15% <100.00%> (+5.07%)	⬆️
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[villebro]

This has definitely caused confusion over the years. Great initiative @mistercrunch !

[eschutho]

/testenv up

[github-actions]

@eschutho Ephemeral environment spinning up at http://35.162.20.252:8080. Credentials are admin/admin. Please allow several minutes for bootstrapping and startup.

[betodealmeida]

Looks good and it's a great improvement!

I wonder if we should standardize the name, though, using sql_rowcount in the backend and something like sqlRowCount in the frontend? (instead of just rowcount)

[mistercrunch]

Yeah I wasn't sure either and there was not clear pattern established for me to follow. Looked that the person who wrote the code before went out of their way to go flat-case (coltypes, colnames, rowcount, ....).

I'm not sure what best practices are and what the most common on our repo is. If I was to take on more refactoring I think i'd tackle something around grouping objects under say a queryMetadata object and passing the object around as much as possible instead of spelling out all the attributes at every step of the way... That would allow say augmenting queryMetadata in the backend with an extra attribute and having it flow all the way through a bunch of objects. Merging for now, and we could revisit the camel-case-on-frontend-policy

[github-actions]

Ephemeral environment shutdown and build artifacts deleted.