Hey Brent for that last question there could be a "driver" difference in connection flags. I've had ARITHABORT cause significant slowness when set to false. Some of the drivers out there set it to false as a default, unlike what SSMS defaults, for instance. Thanks for what you do for us! Always learn something...
@rebornfenix4412
3 ай бұрын
Ya, I was thinking of slow in the application, fast in ssms and going “the set options being different between the drivers would be the first thing I would check”
@mortezasafaee6981
3 ай бұрын
Thanks brent for answering all question in simple english....❤
@legghorn
3 ай бұрын
For the last question: jtds odbc is an pure java driver. I'd guess that the MS odbc driver is writte in C++. That might by the reason for the performance improvement.
@brandonwiese4615
3 ай бұрын
There is in fact a performance benefit to using N'..' Unicode strings in WHERE clauses. I've seen many, many cases where comparing a Unicode column to a non-Unicode string (or even another non-Unicode column) causes SQL Server not to use the available index on the Unicode column.
@BrentOzarUnlimited
3 ай бұрын
Can you email me a repro query to prove that at help@brentozar.com? I'd love to see that.
@brandonwiese4615
3 ай бұрын
@@BrentOzarUnlimited So my original reply was backwards. The problem occurs with VARCHAR columns and Unicode strings in WHERE clauses, where SQL Server decides to do an implicit_convert on the column to NVARCHAR instead of the constant to VARCHAR, thus reading every row and getting an index/table scan instead of an index seek. Sent some screenshots as requested.
@BrentOzarUnlimited
3 ай бұрын
@@brandonwiese4615right, you had it backwards. The scenario we discussed on the video, the N doesn’t matter, as I explained there. But glad you learned something about implicit conversions!
@nofreenamestoreg
3 ай бұрын
I wished you visited Sofia for a tech conference :)
@BrentOzarUnlimited
3 ай бұрын
Is there a big SQL Server conference in Sofia?
@nofreenamestoreg
3 ай бұрын
@@BrentOzarUnlimited I wish, SQL/DATA Saturdays primary
@FlaggedStar
3 ай бұрын
11:40 But won't they need an outage to switch to Enterprise Edition?
@BrentOzarUnlimited
3 ай бұрын
Yes, but it's a one-time change, and then you can do your low-downtime operations as often as you like.
@yltope
3 ай бұрын
At least these "presentations" many times make people feel shame, I'm guessing those stick with them, so you are kind of using the teaching method already 🤔. And give the rest of us a few chuckles along the way 😁
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