Thanks. Indexing as an element to performance was new to me in the 50krecord world I live in.
@michaelkrailo5725
2 жыл бұрын
I like that tool that you created for testing the queries performance and the story at the end with the DBA guy was a lesson well learned.
@neojumpy
3 жыл бұрын
the idea behind the MadMax criterias is very inspiring. I had a similar solution by chance, here the type of solution is shown again very well.
@Ray-ml4oj
3 жыл бұрын
Excellent video Phil! Nice coverage of fundamentals and insights on how the DB Engine 'thinks'. Keep the videos coming.
@AzulonKaiba
2 жыл бұрын
Very interesting recommendation I am beginner about the data engineering stuff and database development. I'll consider the examples to optimize any query.
@codekabinettcomen
2 жыл бұрын
Yes, please do. If these examples apply to your real live queries, you'll see huge performance gains.
@johnclark851
2 жыл бұрын
Great video, but the best part was the tongue-in-cheek comment around the .23 mark!
@codekabinettcomen
2 жыл бұрын
😆 Thank you, John!
@mukhtarali-sq1om
4 ай бұрын
I want to learn
@codekabinettcomen
4 ай бұрын
That's a great goal! I wish you a lot of success.
@mukhtarali-sq1om
4 ай бұрын
How you make sql editor from?
@codekabinettcomen
4 ай бұрын
It's just a "simple" Access form to enter the SQL and another form displaying the results. I'll check whether I can make this publicly available. - Will take some days...
@shadow9449
3 жыл бұрын
Interesting and helpful information. Thank you, Philipp I am not sure if you answered this, but speaking of built-in functions in the WHERE condition, what would be the best way to write a query to find all rows where the [Order Date] is in the future? The most natural way to do it would be "...WHERE [Order Date] > Date()". The engine is not processing anything on the table data using a function so that shouldn't be the performance hit you were discussing at around 19:00-20:00, but I'm wondering if it has to look up today's date for every row then is there a more efficient way to write this?
@codekabinettcomen
3 жыл бұрын
WHERE [Order Date] > Date() is perfectly fine. A function without arguments is always evaluated only once per query *even if it is in the output column list*!
@shadow9449
3 жыл бұрын
@@codekabinettcomen That's good to know. Thanks for the info!
@neojumpy
3 жыл бұрын
I have found with mysql table (MariaDB), the selection-on Is Null is not very efficient. It is better to use (Compagny "") there, only 4 Text-Fields of course. Can you confirm it?
@codekabinettcomen
3 жыл бұрын
I don't use MySQL much at the moment, so I can't confirm. Your criteria example suggests NOT NULL criteria. This might also prevent index usage. Also NULL values might be excluded from the index. - Just guesses.
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