SQL Performance

JULY 1, 2019

The results are technically non-deterministic since SQL Server could validly return any one of the rows in each group. Nevertheless, if you run this query yourself, you are quite likely to see the same result I do: The execution plan depends on the version of SQL Server used, and does not depend on database compatibility level.

C++ 58

C++ Servers Database Performance 58

SQL Server According to Bob

JANUARY 5, 2017

Last March I moved from 22 years in SQL Server support to the SQL Server development team, working on SQL Server on Linux project and reporting to Slava Oks. As Slava highlights in his recent blog post , he also contacted me in early 2015 to assist with supportability of SQL Server on Linux. There are no burning secrets.

Servers 40

Servers Operating System C++ Software Engineering 40

SQL Performance

APRIL 10, 2019

The ISO/IEC 9075:2016 standard, or SQL:2016 in short, introduces support for a profound concept called Row Pattern Recognition (RPR) in SQL. I posted a suggestion to improve SQL Server by adding support for RPR in T-SQL , but I was quite limited in the space that I had to provide the feedback. LAST ( C. NULL NULL 151.00

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C++ Virtualization Servers Code 73

SQL Performance

DECEMBER 9, 2020

L0 AS ( SELECT 1 AS c. Figure 1: Plan for base CTE cardinality of 2.

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C++ Servers Testing Processing 61

SQL Performance

OCTOBER 29, 2019

There are multiple methods to look at poorly performing queries in SQL Server, notably Query Store, Extended Events, and dynamic management views (DMVs). CustomerID , c. Customers c JOIN Sales. CustomerTransactions ct ON c. GROUP BY c. CustomerID , c. Each option has pros and cons. CustomerID = ct.

C++ 74

C++ Database Servers Tuning 74

SQL Server According to Bob

FEBRUARY 10, 2019

. · Failures occur from remote clients or sqlcmd executed directory on the server (/opt/mssql-tools/bin). SQL Server 2017 CU10 does not show behavior. · SQL Server 2017 CU12 exhibits the behavior. Server is a Superdome with lots of CPUs and RAM. Here is an example of a valid SQL Server login. – sqlclr.

Servers 40

Servers Network Database Systems 40

Alex Podelko

OCTOBER 28, 2016

I am looking forward to share my thoughts on ‘Reinventing Performance Testing’ at the imPACt performance and capacity conference by CMG held on November 7-10, 2016 in La Jolla, CA. Tools, using standard languages such as C (e.g. I decided to publish a few parts here to see if anything triggers a discussion. – Cloud.

Performance Testing 100

Performance Testing Technology Technology Testing 100

SQL Server According to Bob

JANUARY 28, 2018

Note: SQL Server can be a client using a linked server, allowing SQL Server to become an APP and/or an RM ). The application then uses the SQL Server client (SQL Server ODBC for this example) to establish a TDS based connection to the target SQL Server (local or remote.). Local Host Name. The olehlp!

Servers 40

Servers Azure Engineering Java 40

Brendan Gregg

OCTOBER 7, 2018

C @ns: [256, 512) 10900 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [512, 1k) 18291 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [1k, 2k) 4998 |@@@@@@@@@@@@@@ | [2k, 4k) 57 | | [4k, 8k) 117 | | [8k, 16k) 48 | | [16k, 32k) 109 | | [32k, 64k) 3 | |. ply is also C, whereas bpftrace is C++. # Attaching 2 probes. ^C

C++ 40

C++ Virtualization Programming Latency 40

Rigor

JANUARY 13, 2020

These are the bestsellers in the web performance field, including the good old Speed Up Your Site (2003) by Andy King; Steve Souders’ Even Faster Web Sites (2009) ; Ilya Grigorik’s High Performance Browser Networking (2013) ; Tammy Everts’ Time is Money (2016) ; and a handful of more recent publications. Responsive and Fast.

Performance 75

Performance Social Media Website Website Performance 75

SQL Performance

OCTOBER 14, 2020

I explained that when SQL Server optimizes a query involving derived tables, it applies transformation rules to the initial tree of logical operators produced by the parser, possibly shifting things around across what were originally table expression boundaries. Here’s the attempted solution using a CTE: WITH C AS. ( FROM Sales.

C++ 140

C++ Servers Code Efficiency 140

SQL Server According to Bob

AUGUST 23, 2016

The creation of the XTP, common access DLL requires SQL Server to generate C code, invoke the C compiler and save the DLL into the XTP directory. Bob Dorr – Principal Software Engineer SQL Server. These are additional steps that a disk based table does not perform.

C++ 40

C++ Software Engineering Servers Code 40

SQL Server According to Bob

DECEMBER 18, 2018

SQL Server relies on Forced-Unit-Access (Fua) I/O subsystem capabilities to provide data durability, detailed in the following documents: SQL Server 2000 I/O Basic and SQL Server I/O Basics, Chapter 2. Be sure to deploy SQL Server 2017 CU6 or newer for best data durability and performance results. “. The Back Story.

Servers 90

Servers Media Cache Storage 90

SQL Performance

OCTOBER 14, 2020

I explained that when SQL Server optimizes a query involving derived tables, it applies transformation rules to the initial tree of logical operators produced by the parser, possibly shifting things around across what were originally table expression boundaries. Here’s the attempted solution using a CTE: WITH C AS. ( FROM Sales.

C++ 52

C++ Servers Code Efficiency 52

SQL Performance

APRIL 20, 2021

This is the third in a five-part series taking a deep dive into the way SQL Server row mode parallel plans start executing. A reminder of the plan ( click to enlarge ): This is the first point in the process so far that an in-flight execution plan is available (SQL Server 2016 SP1 onward) in sys.dm_exec_query_statistics_xml.

C++ 98

C++ Processing Servers Cache 98

Percona

AUGUST 18, 2023

Why do you need multiple instances on the same server? You can have a host with two or three instances configured as a delayed replica of the source server with SQL Delay of, let’s say, 24hr, 12hr, and 6/3hrs. You can run multiple instances on a server to test your backups with the correct version and configs.

Programming 82

Programming Servers Database Hardware 82

SQL Performance

MARCH 20, 2020

We're mid-cycle between releases, where we're not yet hearing about any of the features planned for SQL Server vNext. In SQL Server 2016, STRING_SPLIT solved a long-missing gap in a language that, admittedly, was not intended for complicated string processing. And that is what I want to bring up today.

Database 109

Database Servers C++ AWS 109

Percona

JANUARY 17, 2019

I will compare AWS Aurora with MySQL (Percona Server) 5.6 84.1 | | version_comment | Percona Server (GPL), Release 84.1, 84.1 | | version_comment | Percona Server (GPL), Release 84.1, AWS Aurora (based on MySQL 5.6) MySQL on ec2. MySQL on ec2.

Cache 46

Cache C++ AWS Airlines 46

SQL Performance

SEPTEMBER 5, 2019

I briefly mentioned that batch mode data is normalized in my last article Batch Mode Bitmaps in SQL Server. You will need SQL Server 2016 (or later) and Developer Edition (or equivalent) to reproduce the results shown here. c = COUNT_BIG ( * ) FROM #T AS T WHERE 1 = ( SELECT 1 ) -- Avoid trivial plan.

Performance 81

Performance C++ Storage Servers 81

SQL Performance

SEPTEMBER 2, 2021

SQL Server 2016 brought us STRING_SPLIT , a native function that eliminates the need for many of the custom solutions we’ve needed before. I’ve written several articles about this function (and STRING_AGG, which arrived in SQL Server 2017) since this post was written: Performance Surprises and Assumptions : STRING_SPLIT().

C++ 59

C++ Servers Testing Database 59

SQL Performance

SEPTEMBER 25, 2019

For modern versions of SQL Server, this essentially means that all key columns in an index spool must be of a comparable type, no more than 900 bytes* in total, with 64 key columns or fewer. c1 UNION SELECT NULL ) AS U ) AS CA ( c ) ; Notice the Stream Aggregate below the Lazy Index Spool. Optimizer Rules.

Performance 104

Performance Cache Servers Education 104

Scalegrid

AUGUST 15, 2019

In 2014, we discussed 4 of the top MongoDB GUIs: MongoVue, MongoHub, RockMongo, and Robo 3T (formerly Robomongo), and again in 2016: MongoDB Compass, Robo 3T, Studio 3T, and MongoBooster. Should have an excellent way to measure server and query performance. Import data from RDBMS like MySQL, PostgreSQL, and SQL Server.

Database 40

Database Servers Monitoring Availability 40

Brendan Gregg

SEPTEMBER 5, 2017

LTS (April 2016). I wrote about it in a previous post, [DTrace for Linux 2016]. Hit Ctrl-C to end. ^C C operation = 'read' usecs : count distribution 0 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 4479 | *| 8 -> 15 : 1028 | | 16 -> 31 : 14 | | 32 -> 63 : 1 | | [.]. Oracle VM Server is based on Xen. amazon").

Virtualization 76

Virtualization AWS Engineering Hardware 76

Randon ASCII

FEBRUARY 25, 2018

In September of 2016 we started noticing random failures when building Chrome – 3 out of 200 builds of Chrome failed when protoc.exe, one of the executables that is part of the build, crashed with an access violation. The next step was a custom C++ program that opened the just-linked exe and called FlushFileBuffers on it.

Programming 79

Programming Hardware Cache Code 79

Smashing Magazine

JULY 6, 2021

With Luminary’s 21 years of experience in the digital space, my experience of 17 years in the CMS space as well as our focus on Headless since 2016, here are my two cents on what you should look out for. Things To Consider When Choosing A Headless CMS. Microservices architecture. Omnichannel. For content authors.

Cache 143

Cache Website Mobile Google 143

Smashing Magazine

OCTOBER 26, 2018

When it comes down to how WordPress is programmed, one thing is certain: it doesn’t follow the M odel- V iew- C ontroller (MVC) design pattern that many developers are familiar with. on December 6th, 2016. If you decide to use the method described in this article, be sure you know how to fortify your server security.

Cache 78

Cache Website Speed Database 78

Alex Russell

MAY 9, 2022

This blindspot usually extends up to the C-suite. Teams achieving this level of discipline about performance begin to eliminate variance from their lab data by running tests in "less noisy" environments than somewhere like a developer's laptop, a shared server, or a VM with underlying system variance.

Performance 86

Performance Latency Metrics Engineering 86

Smashing Magazine

JANUARY 21, 2019

An API is the communication channel for an application to load data from the server. This relationship can be expressed through an associative array (an array of key => property) on the server-side, in which each module states its name as the key attribute and its inner modules under the property modules. Large preview ).

Social Media 64

Social Media Database Media Website 64

Percona

JANUARY 14, 2019

scala','currency','println'] ? ? voting','maven'] ? ? compose','xamarin','markdown','scrum','comic'] ? ? china','sourceforge','subscription','chinese','kotlin'] ? ? systemd','gitlab','autotldr'] ? ? refugees','refugee','sanders','debates','hillary','removal','participating','removed','greece','clinton'] ? ?

Database 40

Database Analytics Blockchain Healthcare 40