
How a SQL database works - datelligence
http://calpaterson.com/how-a-sql-database-works.html
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metalliqaz
I find it somewhat disappointing that these kinds of tutorials always use such
simplistic demo data. I don't care about a database with 3 rows and 4 columns.
I wish the authors could find a way to illustrate what a larger, more
realistic database looks like. Like, a database that would actually need an
index.

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purgatio
Alternatively, analytics databases don't use indices by design, as for most
queries they need to shuffle entire datasets anyways. For example,
[https://dbdb.io/db/vertica](https://dbdb.io/db/vertica): "Indexes are not
support in Vertica."

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paulddraper
Indexes are part of the SQL standard, so they are certainly pertinent for "SQL
database" discussion.

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anarchyrucks
Introduction to Database Systems (CMU) [0] should be useful to anyone who
wants to learn about how relational databases work.

[0]
[https://www.youtube.com/playlist?list=PLSE8ODhjZXjbohkNBWQs_...](https://www.youtube.com/playlist?list=PLSE8ODhjZXjbohkNBWQs_otTrBTrjyohi)

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brazzy
Nice. Now explain query optimizers.

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calpaterson
I'll try! :) I wanted to cover this material because I found that most of the
"how SQL works" intros discuss query planning but I think knowing the
underlying datastructures gives people pretty useful intuition.

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brazzy
Grace hash join would be another major topic to cover first.

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draw_down
Good thing we cut that "a" out of the title. Saved me so much reading time,
and at the low cost of making the title ungrammatical!

(Seriously, why keep doing this?)

