SQL Server According to Bob

FEBRUARY 22, 2018

Prior to SQL Server 2017 CU4 for Linux (Linux only) the generation of a sequential UUID may not function as expected. SQL Server’s NewSequentialId () calls the Windows API UuidCreateSequential , which is limited in SQLPAL, prior to the CU 4 update. Server B may be generating uuids that sort before those from Server A.

Servers 40

Servers Software Engineering Database Network 40

SQL Performance

AUGUST 11, 2021

One is using a function called DATE_BUCKET , which at the time of writing is only available in Azure SQL Edge. Another is using a custom calculation that emulates the DATE_BUCKET function, which you can use in any version, edition, and flavor of SQL Server and Azure SQL Database. DATE_BUCKET. OrderValues. 2018 408 617085.30

Azure 139

Azure Code Database Servers 139

SQL Performance

FEBRUARY 12, 2020

I'll continue using the sample database TSQLV5 like last month in some of my examples. You can find the script that creates and populates this database here , and its ER diagram here. Unfortunately, this clause is not yet available in T-SQL. 10249 2017-07-10 10252 2017-07-11 10250 2017-07-12.

C++ 120

C++ Code Servers Database 120

SQL Performance

DECEMBER 11, 2019

Even among people who do have a good grasp of relational theory and SQL, you will hear very strong opinions both in favor and against using NULLs in your database. Finally, I cover missing standard features related to NULL handling in T-SQL and suggest alternatives that are available in T-SQL. NULL as a marker for a missing value.

Best Practices 117

Best Practices C++ Database Code 117

SQL Performance

MARCH 17, 2020

This follow-up post revisits the question for SQL Server 2019, using a larger number of rows. I will be using the 50GB Stack Overflow 2013 database , but any large table with a low number of distinct values would do. The Stack Overflow 2013 database comes without nonclustered indexes to minimize download time. Test Environment.

Servers 86

Servers Tuning Database Efficiency 86

SQL Performance

JUNE 5, 2019

One of the more perplexing problems to troubleshoot in SQL Server can be those related to memory grants. SQL Server’s optimizer estimates how much memory is needed, and the query must obtain the memory grant in order to start executing. ALTER DATABASE [ WideWorldImporters ] SET QUERY_STORE = ON ; GO. sort, hash).

Servers 41

Servers Cache Database Metrics 41

SQL Server According to Bob

JANUARY 28, 2018

Resource Manager – Database, File System, with ACID capabilities. Note: SQL Server can be a client using a linked server, allowing SQL Server to become an APP and/or an RM ). Once the connection to SQL Server is established the APP executes the odbc! Microsoft specific implementation for DTC using (OLE-TX).

Servers 40

Servers Azure Engineering Java 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. “.

Servers 90

Servers Media Cache Storage 90

Percona

JULY 7, 2023

With the average cost of unplanned downtime running from $300,000 to $500,000 per hour , businesses are increasingly using high availability (HA) technologies to maximize application uptime. Unfortunately, using certain open source database software as part of an HA architecture can present significant challenges.

Availability 85

Availability Open Source Architecture Database 85

Brendan Gregg

NOVEMBER 29, 2017

At Netflix, we've been using these technologies as they've been made available for instance types in the AWS EC2 cloud. But not all workloads: some are network bound (proxies) and storage bound (databases). ## 5. Xen AWS 2017 In 2015, AWS launched c4, which used hardware virtualization for EBS volumes. The first was c3.

Virtualization 111

Virtualization AWS Hardware Storage 111

KeyCDN

NOVEMBER 8, 2018

We also recommend using a free program like KeePass or KeePassX which allow you to generate secure passwords and store them in a database locally on your computer. Varonis) In 2017 there was a 13 percent overall increase in reported system vulnerabilities.

Transportation 47

Transportation Website Google Infrastructure 47

SQL Server According to Bob

FEBRUARY 13, 2020

​​​​ A utility would issue the dbcc freeze to stop the I/O activity for the database. ​​ When the utility attempted to issue the thaw command the command would be queued, and the database could not return to an operational state until SQL Server was restarted.

Servers 40

Servers Availability Transportation Database 40

Percona

AUGUST 15, 2023

This blog was originally published in February 2017 and was updated in August 2023. MySQL replication is a process in which data from a primary MySQL database is copied and sent to one or more secondary databases, known as replicas. Set the server-id to a unique value. Start the replica server’s replication process.

Servers 52

Servers Database Availability Traffic 52

Scalegrid

APRIL 2, 2019

PostgreSQL is an open source relational database system that has soared in popularity over the past 30 years from its active, loyal, and growing community. For the 2nd year in a row, PostgreSQL has kept the title of #1 fastest growing database in the world according to the DBMS of the Year report by the experts at DB-Engines.

Database 185

Database Cloud Open Source Azure 185

Brendan Gregg

NOVEMBER 28, 2017

At Netflix, we've been using these technologies as they've been made available for instance types in the AWS EC2 cloud. But not all workloads: some are network bound (proxies) and storage bound (databases). ## 5. Xen AWS 2017 In 2015, AWS launched c4, which used hardware virtualization for EBS volumes. The first was c3.

Virtualization 40

Virtualization AWS Hardware Storage 40

SQL Performance

MAY 13, 2020

As a result, in the same level of nesting, column aliases that you define in the SELECT clause are only available to the ORDER BY clause. They are not available to the rest of the query clauses. In my examples I'll use a sample database called TSQLV5. Derived tables. It then reports the base type as requested.

C++ 143

C++ Code Design Servers 143

SQL Performance

JULY 9, 2019

This feature is currently not available in T-SQL. I posted a suggestion to improve SQL Server by adding support for nested window functions. At the date of this writing, there's not much information available out there about the true standard nested window functions. 2 2017-09-18 88.80 10248 85 2017-07-04 440.00

Servers 83

Servers Availability Database Code 83

Percona

DECEMBER 21, 2023

The efficiency of database queries in MySQL can make all the difference in the performance and responsiveness of applications. A Query Execution Plan is the way a database chooses to run a specific query. The global default can be set at server startup. This variable has global and session values and can be changed at runtime.

Efficiency 106

Efficiency Database Open Source Performance 106

The Symphonia

DECEMBER 6, 2017

Traffic shaping / canary deployment was pre-announced at Serverless Conf NYC in October, and this is now available. there’s no inline debugging available in the Lambda Console.) without web app servers?—?to Serverless Aurora promises to be the SQL Database to partner with Lambda that we’ve been hoping for.

Serverless 40

Serverless Lambda AWS Traffic 40

SQL Performance

JANUARY 8, 2020

I'll continue using the sample database TSQLV5 like last month in some of my examples. You can find the script that creates and populates this database here , and its ER diagram here. A much more elegant option is to use the CONCAT_WS function, which was introduced in SQL Server 2017. NULL treatment inconsistencies.

Design 65

Design C++ Code Database 65

SQL Performance

JANUARY 23, 2020

Tom Davidson, Opening Microsoft's Performance-Tuning Toolbox SQL Server Pro Magazine, December 2003. Waits and Queues has been used as a SQL Server performance tuning methodology since Tom Davidson published the above article as well as the well-known SQL Server 2005 Waits and Queues whitepaper in 2006.

Tuning 115

Tuning Servers Monitoring Hardware 115

Percona

SEPTEMBER 1, 2023

This blog was originally published in October 2017 and was updated in September 2023. Database architects working with MongoDB encounter specific challenges related to database systems and system growth. In a sharded cluster, each shard acts as an independent database responsible for storing and managing specific data.

Best Practices 73

Best Practices Traffic Database Servers 73

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. top(1) showed that only the Cassandra database was consuming CPU. This server is spending about a third of its CPU cycles just checking the time! What on Earth is Ubuntu doing that results in 30% higher CPU time!?

Speed 126

Speed Java AWS Virtualization 126

The Morning Paper

NOVEMBER 8, 2020

USENIX is a nonprofit organisation committed to making content and research freely available – both conference proceedings and the recorded presentations of their events. Back in 2017 the engineering team at Facebook had a problem. In Facebook’s implementation of NativeLoglet, seal simply sets a bit on a quorum of servers.

Virtualization 126

Virtualization Latency Storage Systems 126

SQL Performance

AUGUST 27, 2019

On August 7, 2019, AMD finally unveiled their new 7nm EPYC 7002 Series of server processors, formerly code-named "Rome" at the AMD EPYC Horizon Event in San Francisco. This is the second generation EPYC server processor that uses the same Zen 2 architecture as the AMD Ryzen 3000 Series desktop processors.

Servers 52

Servers Benchmarking Virtualization Architecture 52

Particular Software

MARCH 15, 2021

As popular as NoSQL databases have become, you’d be hard-pressed to find a successful business that isn’t running some flavor of SQL somewhere. For NServiceBus systems, our SQL Persistence package allows you to use whatever flavor of SQL works best for you, supporting dialects for Microsoft SQL Server, MySQL, PostgreSQL, and Oracle.

Transportation 52

Transportation Azure Database Servers 52

All Things Distributed

OCTOBER 2, 2017

Today marks the 10 year anniversary of Amazon's Dynamo whitepaper , a milestone that made me reflect on how much innovation has occurred in the area of databases over the last decade and a good reminder on why taking a customer obsessed approach to solving hard problems can have lasting impact beyond your original expectations.

Internet 128

Internet Internet AWS Performance 128

Abhishek Tiwari

DECEMBER 1, 2017

At re:Invent 2017, Amazon Web Services (AWS) announced Amazon Time Sync Service which provides a highly accurate and reliable global time reference. This service is immediately available in all AWS regions. TrueTime was introduced to support Spanner - Google’s globally distributed, and synchronously-replicated database.

AWS 55

AWS Google Database Virtualization 55

SQL Performance

NOVEMBER 4, 2021

First introduced in SQL Server 2017 Enterprise Edition, an adaptive join enables a runtime transition from a batch mode hash join to a row mode correlated nested loops indexed join (apply) at runtime. Like any hash join, an adaptive join reads all rows available on its build input and copies the required data into a hash table.

Servers 98

Servers Design Database Code 98

SQL Performance

FEBRUARY 3, 2020

I was smart and took a backup of the original source, and created a procedure to revert the database back to its initial state. The downside to the latter is that, in SQL Server 2017, you cannot run this online… but you will be able to in 2019.

Speed 113

Speed Processing Servers Storage 113

Percona

AUGUST 5, 2023

This blog was originally published in July 2017 and was updated in August 2023. Partitioning is a way in which a database (MySQL in this case) splits its actual data down into separate tables but still gets treated as a single table by the SQL layer. So, What is MySQL Partitioning? Additionally, MySQL 8.0

Strategy 40

Strategy Storage Database Best Practices 40

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. top(1) showed that only the Cassandra database was consuming CPU. This server is spending about a third of its CPU cycles just checking the time! What on Earth is Ubuntu doing that results in 30% higher CPU time!?

Speed 40

Speed Java AWS Virtualization 40

Alex Russell

MARCH 6, 2021

TL;DR: A lot has changed since 2017 when we last estimated a global baseline resource per-page resource budget of 130-170KiB. To update our global baseline from 2017, we want to update our priors on a few dimensions: The evolved device landscape. Modern network performance and availability. The Moto G4 , for example. Hard Reset.

Performance 124

Performance Network Cache Metrics 124

Percona

JANUARY 17, 2019

On multi-core machines – which is the majority of the hardware nowadays – and in the cloud, we have multiple cores available for use. I will compare AWS Aurora with MySQL (Percona Server) 5.6 84.1 | | version_comment | Percona Server (GPL), Release 84.1, With faster disks (i.e. MySQL on ec2.

Cache 47

Cache C++ AWS Airlines 47

O'Reilly

MARCH 23, 2023

It’s clear that ChatGPT is not your run-of-the-mill automated chat server. An API for ChatGPT is available. GPT-3 and GPT-4 are not open source, but are available for free and paid access. Poe is a chat app based on Claude, and available through Quora; there is a waiting list for access to the Claude API. It’s much more.

Google 104

Google Open Source Programming Code 104

SQL Performance

APRIL 8, 2019

Back on December 5, 2017, Microsoft announced that they were using AMD EPYC 7551 processors in their storage-optimized Lv2-Series virtual machines. These VMs are not available in all regions, so you will want to check the availability in the Azure region that you are interested in using. AMD EPYC 7551 Details.

Azure 42

Azure Virtualization Storage Benchmarking 42

SQL Performance

APRIL 23, 2019

In SQL Server 2012, grouped (vector) aggregation was able to use parallel batch-mode execution, but only for the partial (per-thread) aggregate. SQL Server 2014 added the ability to perform parallel batch-mode grouped aggregation within a single Hash Match Aggregate operator. instructions are available. Introduction.

Servers 67

Servers Testing Metrics Storage 67