Database Indexing for Dumb Developers

This video explains what happens under the hood when indexing a database and explains why it can lead to performance benefits.

[FreeTheFresh]

This is far and away the best indexing video I have watched. Every other one barely goes into how indexing works under the hood, or use analogies that don't really make sense. Keep up the awesome content!

[futhedude]

recap:
7:08 full table scan
12:26 binary search
13:56 we shouldn't add index at everything

[satyajeetsahu]

This video explained indexing so simply that I can't forget it ever!!!

[brianfan]

BEST Indexing explanation video on YouTube

[williamse.barreras.]

Study it tooo long ago, recently my boss put me on the spot with ‘what is an index in db’ haha. Now I know, thanks mate. Good video

[hiteshsuthar]

Now i understand this system design term... Please make more videos on cool stuffs like this.

[toluajise]

In my opinion, this explanation presents a very clear analysis and straightforward approach to database indexing.

[timmytesla]

I have watched numerous videos, but this is the best explanation so far. Kudos.

[stratboy]

Finalyy a tut that really explains what indexes are... The only one till now. Than you!

[paulo__vieira]

This was way too easy to understand. Thank you for the explanation.

[gadgetboyplaysmc]

More on the performance hit of indices on WRITES. How does it work?

Does it:
A. Insert the new row in the TABLE (O(1)). Find where the index should be placed (O(logn)), insert it there (O(1)).

Or does it:
B. Insert the new row in the TABLE (O(1)). Query the whole TABLE again (constant). Sort it again (O(idk)). Save it in the index (O(1)).

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I'm guessing A, but I'm not even sure if that's possible lol. I guess the "finding where the index should be placed" would be the slow part and most likely it would be equivalent as doing the same SELECT query for that column as well? Since you mentioned that SELECT is O(logn):
Essentially writes would be O(logn). Would that be, correct?

[santoshpoudel]

i have looked up to many videos and just came across this detailed best explanation

[agguLi]

Thank you very much for the video.
I have one question:
What happens, if I execute a query on a non indexed column? Based on your explanation, the Blocks stay on disc and when B and I are found by an index, they can be loaded explicitly.
When there is no index and I execute a query, is the "load from disc into memory" operation done at runtime?
Thanks a lot

[theyayaa]

I came for indexing, but couldn't help but notice that Laith is making $54 million while my boy Todd is making $27k....Laith must be the CEO

[futhedude]

Great explaination, can you do B-tree and Hash in DB Indexing?

[als]

can you do something like this for mongoDB?

[MONTI]

Hands down the best tutorial on index❤

[tpa]

Is this somehow how it works in Windows when it indexes files for file search?

[dgimop]

Watch this video on 1.25x speed. You're welcome!

[nullpointer]

But even though we significantly reduced the search time, we have increased the time required to add a record right?