ChrisM@Work

Forum Replies Created

Viewing 15 posts - 106 through 120 (of 10,143 total)

RE: Improve performance of a query by milliseconds. Should I loop the query to extrapolate the stats ?

Gamleur84 - Wednesday, March 27, 2019 1:45 AM
Hi,
I am a query that takes 0.26 seconds to complete in average. The challenge is...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 27, 2019 at 8:18 am

#2033947
RE: A question about the EXISTS operator

drew.allen - Monday, March 25, 2019 10:52 AM
ReamerXXVI - Monday, March 25, 2019 2:23 AM
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 25, 2019 at 10:56 am

#2031699
RE: A question about the EXISTS operator

According to BOL, EXISTS "Returns TRUE if a subquery contains any rows."
Your...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 25, 2019 at 5:08 am

#2025338
RE: t-sql 2012 sum of several fields

That query would benefit from a refactor - perhaps it's been worked over and extended one too many times. Something like this will work:
; WITH
Sped_Services AS...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 21, 2019 at 8:49 am

#2025115
RE: How to return a value if an INNER JOIN isn't satisfied?

You'd almost certainly get better performance by combining both of those aggregates into one, like this:
SELECT
'North Central' AS Region,
Grouping_Level,
(nh_MTDValue - nn_MTDValue) AS MTDValue,
(nh_MTDTarget - nn_MTDTarget)...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 21, 2019 at 2:49 am

#2025085
RE: Pitfalls of cross-database views?

johnzabroski - Monday, March 18, 2019 5:34 PM
ChrisM@Work - Monday, March 18, 2019 10:58 AM
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 19, 2019 at 2:36 am

#2024868
RE: Pitfalls of cross-database views?

Why not separate functionality using different schemas rather than databases?
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 18, 2019 at 10:58 am

#2024799
RE: Are the posted questions getting worse?

Eirikur Eiriksson - Monday, March 18, 2019 9:16 AM
below86 - Monday, March 18, 2019 8:38 AM
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 18, 2019 at 9:23 am

#2024776
RE: How can I offload the compute of SUM operation ?

Gamleur84 - Monday, March 18, 2019 2:06 AM
I am also considering a covered index.
How many rows are in the table? How many...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 18, 2019 at 9:16 am

#2024771
RE: Loading CSV file into Multiple tables

Jeff Moden - Thursday, March 14, 2019 9:07 AM
poratips - Wednesday, March 13, 2019 8:24 PM
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 14, 2019 at 9:17 am

#2024460
RE: T-SQL correlated queries

Toby Harman - Thursday, March 14, 2019 12:03 AM
Thanks Stuart
So the subquery becomes (SELECT t1.c1 from t2) which makes even less sense...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 14, 2019 at 2:18 am

#2024417
RE: Can I hint a join order or can I hint the first index seek ?

-- Write your query the simplest way BEFORE attempting to optimise.
-- Don't use SELECT *, attempts at optimisation will most likely fail
-- because ordinary indexes usually consist of...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 12, 2019 at 2:58 am

#2024173
RE: Public Facebook group for peer to peer mental illness support

Joined. My daughter's on the spectrum. Thanks for sharing, Robert.
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 8, 2019 at 2:09 am

#2023919
RE: Quering a Always Encrypted Column with a already encrypted value

christian_t - Thursday, March 7, 2019 6:14 AM
currently this encrypted deterministic, so same value = same varbinary.
If it is possible, what would...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 7, 2019 at 6:20 am

#2023793
RE: Quering a Always Encrypted Column with a already encrypted value

If you're talking about SQL Server column-level encryption then no, it won't work. Encrypting a single value, say a credit card number, will result in any one of a very...
^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

March 7, 2019 at 6:09 am

#2023791

Viewing 15 posts - 106 through 120 (of 10,143 total)