
Data Blending: combine multiple sources into one dataset with Tableau or Alteryx - numizmat
https://blog.panoply.io/data-blending-what-it-is-and-how-to-do-it
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jbradley311
Tableau user here. It took me a while to get my head around the concept
of'data blending' as the documentation a while back was aimed at non-technical
users (the beauty of Tableau is that it's so easy to pick up and start making
data visualisations with). I'm not sure about Alteryx, but in Tableau, a blend
is fundamentally just a left outer join (so everything in the left table is
always returned by the query). The clever bit is that Tableau will aggregate
the data in the left table based on the fields (and therefore level of
granularity) you choose from the right table(s) before the join is done.
Hence, data blending is very useful when you want to join datasets that are at
different levels of granularity. One thing to keep in mind though is, as an
outer join is done between the left tables and right table(s), performance can
quickly reduce as the sizes of the table(s) in your query get bigger.

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kfk
Just my 2 cents of managing a an analytics team that works daily with Tableau
and Alteryx: 1) Alteryx is super expensive and can be replaced with Jupyter
Lab and Python, those that do Alteryx well can also do basic data prep in
python; 2) forget Tableau for anything other than fancy, online, dashboards
(so forget pivot tables, email notifications and pdfs that look good)

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marianoguerra
what do you mean by "forget pivot tables, email notifications and pdfs that
look good".

they don't work? are expensive? hard to use? limited?

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kfk
Tableau straight out refuses to make tables that look good because they want
users to do charts. So if your users want cross tab looking reports like
Pivots, Tables, etc., you'll be left with a very limited solution. Tableau
does also very limited notifications and those are normally "subscribed" by
users, not centrally managed. Finally, no pdf or print out or screenshot ever
looks as good as those from Excel, I don't know why, but they know it is a
problem and they still think it's ok. In summary Tableau is about the "Tableau
way" which is great if you have the right type of user, but completely sucks
if you don't. For instance, if you are trying to move people away from Excel,
Tableau is too much of a leap and will hurt your adoption of an online
solution. Things like "SeekTable" are better if all you need is moving away
people from crazy Excel files.

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Tarq0n
In my experience doing data transformations in Tableau is almost always a
mistake. It's opaque what's actually happening and you can't version control
the actual operations. Instead, preprocess data into a view in your database
or with a script and read that into Tableau.

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dhkxh
Not sure why they've grouped together Alteryx and Tableau - they're completely
different pieces of software used for completely different purposes. By the
time your dataset gets to Tableau it better be ready for visualisation with
minimal changes.

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x86_64Ubuntu
I'm a QlikSense developer, so I've always wondered about the other
technologies in the BI and Data Engineering Realm. It's hard to do what you
can do with programming languages in trying them out, because they are all so
expensive.

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hestefisk
Alteryx / Tableau is indeed a powerful combo. But it is also bloody expensive.

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kfk
Correct, I am definitely going to replace Alteryx with Jupyter / Python and
maybe with vega we could replace Tableau at one point too.

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realfaux
Just learned about vega from your comment. It seems very cool (coming from a
person who loves D3). But replacing Tableau with a higher level D3... seems
like you'd lose in man hours what you make up in subscription cost savings...

