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SQL Server Cardinality 

Bert Wagner
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When building indexes for your queries, the order of your index key columns matters. SQL Server can make the most effective use of an index if the data in that index is stored in the same order as what your query requires for a join, where predicate, grouping, or order by clause.
But if your query requires multiple key columns, which should you list first in your index key column definition?
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30 сен 2024

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Комментарии : 16   
@gabesusman4592
@gabesusman4592 2 года назад
I was desperately hoping the cardinal would know nothing about cardinallity and leave
@kaushikbudi8819
@kaushikbudi8819 6 дней назад
Doesn't this contradict the other video "Does The Order Of Index Columns Matter? " info
@sql3051
@sql3051 5 лет назад
Bert, another interesting topic, so when creating an index do you start by querying the table for row counts on columns that you are considering to place in the index? Maybe in another video you can explain a little deeper. Thank you for all the interesting topics. Look forward every Tuesday to see your next subject matter.
@MZ-uv3sr
@MZ-uv3sr 4 года назад
Oaf, I liked your other videos I've seen so far, but I could do without the cartoon cardinals and cheese lol. Still good info
@ReuelRamos
@ReuelRamos 5 лет назад
Found your channel just now and it looks neat. I find it somewhat difficult to find concise content and well organized about database out there. Looking forward for your content. 👍🏻👍🏻👍🏻
@Mahmoud-ys1kt
@Mahmoud-ys1kt Год назад
have a like before i finish the video
@aler.4108
@aler.4108 4 года назад
cool. Love you, Man! :)))
@kuzco7061
@kuzco7061 6 месяцев назад
I must say, I was kinda skeptical but this really helped me get a quick overview of Cardinality. Thank you!!!
@vklude
@vklude Год назад
amazing 😂😂😂
@aamirkarim
@aamirkarim 5 лет назад
Will you make a normalisation video till the last degree
@satori8626
@satori8626 Год назад
Awesome video :)
@dammdanyal
@dammdanyal 2 года назад
This deserves more love!
@SandraDee590
@SandraDee590 2 года назад
This is excellent!
@ulysses1904
@ulysses1904 5 лет назад
Good info. So please clarify, is high cardinality the same thing as low density? Watching Itzik Ben-Gan's Cross Apply videos I'm assuming low density = large number of unique values = high cardinality (like customers in an orders table). And high density = small number of unique values = low cardinality (like shippers in an orders table)?
@OddvarEikli
@OddvarEikli 5 лет назад
Check out this article: blogs.msdn.microsoft.com/bartd/2011/01/25/query-tuning-fundamentals-density-predicates-selectivity-and-cardinality/
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