Window Functions vs Group By

Really nice video

hey, u're great.

chutiye.. bak bak bak kar raha hai sirf

Quick question
Does something similar happens with PostgreSQL?

Hey Bert, great video. Quick question though, is tempdb written to disk or would it be stored only in RAM, and is that dependent on the database/configuration? Is there any reason why we can't store it in RAM(if it isn't already)?

Wow, this was eye opening. Had never seen an execution plan before.

Amazing job!!!!

Is this the same for MySQL?

Thanks a ton!!!!

Great Video! enjoyed it a lot, much beneficial. how did u learn to optimize SQL ?

Great content, man. You’ve got really kind eyes

Btw, are we sure optimizer did not cached previous result in a way so it reduces time spent?

Very useful, thanks!

How to get stackoverflow questions alerts to answer a specific badge ?

Wow a good video on SQL..never thought Id see the day.

Commenting after the first minute because, regardless of how the rest of the video goes, I appreciate that someone is focusing on solving problems when your only lever to pull is your query.

Another great video. Thank you! Would you consider doing a video (or videos) diving into the details of writing the queries? I know very little about Windows Functions and have always struggled with this type of query using Group Bys. I never seem to get it just right.

Do you have an example of how to use a group by instead of a window function with unbounded range preceding? It seems like you have to use the window function in that case, right?

As a full stack dev (i.e. master of nothing) I find these types of videos really useful. I can understand the SQL and what it is supposed to do, but not always why or how.

Bert, I know... but it is very easy to say what is wrong and what is right in such kind of situations... ;)

"Black Magic" I say!! I'm downloading the DB now so I can try this out. Thanks for an awesome video. Love these optimization vids. Funny how few developers out there do the basics; change RBAR to set based statements, read the execution plans, and just try to reduce the number of rows. Instead, they just climb in and start slashing at code and configuring SQL and Hardware... It keeps us consultants in business :)

If I may, can I suggest a video on some useful DMVs? I love the "missing index","index usage" and "exec query stats" ones, but there may be more really good ones out there that we can add to our toolkits - there are just so many :)

This is great, I often find myself trying both windowed functions and group by, but never really understanding the differences they can potentially have in the optimizer.

Thanks for putting out these videos. Very informative, I would not have guessed that the optimizer would come up with such different plans.