SQL Performance

MARCH 10, 2021

BatchMe ( col1 INT NOT NULL , INDEX idx_cs CLUSTERED COLUMNSTORE ) ; And here’s the code with the definition of the dbo.GetNumsAlanCharlieItzikBatch function: CREATE OR ALTER FUNCTION dbo. GetNumsAlanCharlieItzikBatch ( @low AS BIGINT = 1 , @high AS BIGINT ) RETURNS TABLE.

C++ 134

C++ Testing Code Servers 134

SQL Performance

JANUARY 13, 2021

L0 AS ( SELECT 1 AS c. Here’s the function’s definition: CREATE OR ALTER FUNCTION dbo. L0 AS ( SELECT 1 AS c. For this reason, compile times should definitely be taken into account—especially when using the function very frequently with small ranges. This process can have both negative and positive implications.

C++ 113

C++ Code Testing Processing 113

SQL Performance

JULY 27, 2021

Continuing my series of articles on latches, this time I’m going to discuss the DBCC_OBJECT_METADATA latch and show how it can be a major bottleneck for consistency checks prior to SQL Server 2016 under certain circumstances. But remember, this bottleneck only happens for versions of SQL Server earlier than SQL Server 2016.

C++ 54

C++ Servers Database Code 54

SQL Performance

DECEMBER 9, 2020

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

C++ 114

C++ Servers Testing Processing 114

SQL Performance

JULY 13, 2022

L0 AS ( SELECT 1 AS c. But what if you require a deterministic definition of the frame with guaranteed repeatable results? To test the performance of the solutions, you’ll need a larger set of sample data. Orders WITH ( TABLOCK ) ( orderid , orderdate , empid , custid , qty ) SELECT N.

C++ 112

C++ Code Azure Database 112

SQL Performance

APRIL 13, 2022

Note the definition of the primary key constraint based on the composite key (grp, ord), which results in a clustered index based on the same key. L0 AS ( SELECT 1 AS c. My test machine has four logical CPUs, running SQL Server ® 2019 Enterprise. I used a SELECT INTO statement to write the result into a temporary table.

C++ 136

C++ Strategy Testing Servers 136

SQL Performance

MAY 11, 2022

Naturally, if a partitioning or ordering element doesn’t appear in the window function, you omit that part from the index definition. I ran all the examples on SQL Server ® 2019 Developer, where batch-mode on rowstore is available. But what about queries involving multiple window functions with different ordering needs?

C++ 133

C++ Database Servers Code 133

SQL Performance

JUNE 10, 2020

In my coverage of the physical treatment of named table expressions in the series I focus on the treatment in Microsoft SQL Server and Azure SQL Database. Recall that what triggered this series is some confusion that exists in the SQL Server community around named table expressions.

C++ 109

C++ Database Servers Code 109

SQL Performance

JUNE 10, 2020

In my coverage of the physical treatment of named table expressions in the series I focus on the treatment in Microsoft SQL Server and Azure SQL Database. Recall that what triggered this series is some confusion that exists in the SQL Server community around named table expressions.

C++ 93

C++ Database Servers Code 93

SQL Performance

DECEMBER 9, 2020

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

C++ 61

C++ Servers Testing Processing 61

Percona

OCTOBER 10, 2023

Your MySQL connection id is 256 Server version: 8.0.32-24.2 Copyright (c) 2009-2023 Percona LLC and/or its affiliates Copyright (c) 2000, 2023, Oracle and/or its affiliates. Type 'c' to clear the current input statement. Type 'c' to clear the current input statement. Commands end with ; or g. drop_triggers:10000:0.25,copy_rows:10000:0.25,swap_tables:10000:0.25,update_foreign_keys:10000:0.25,analyze_table:10000:0.25

Database 95

Database Performance C++ Engineering 95

Sutter's Mill

JANUARY 11, 2021

C++20 supports two main assertion facilities… For each one, briefly summarize how it works, when it is evaluated, and whether it is possible for the programmer to specify a message to be displayed if the assertion fails. 5] For conditions, it’s up to us to make sure it’s true.) Bonus: [[assert: ?

C++ 58

C++ Programming Code Testing 58

Percona

MARCH 7, 2019

The server is a small instance: Models | 6xIntel(R) Xeon(R) CPU E5-2430 0 @ 2.20GHz 10GB RAM This symptom can be caused by various different reasons. There could be more, but this particular query was definitely hurting the performance of the server. We needed to reduce the high CPU usage on MySQL. Increase QPS by 2x.

C++ 100

C++ Traffic Servers Monitoring 100

All Things Distributed

DECEMBER 1, 2016

AWS Batch : Fully- managed batch processing at any scale, with no batch processing software to install or servers to manage. We also added C# support for AWS Lambda. We're excited to see how customers you will put these new features to work. *: Sean Connery is the definitive Bond.

AWS 162

AWS Development Lambda Open Source 162

Alex Podelko

OCTOBER 28, 2016

While protocol-level recording/playback was (and still is) the mainstream approach to testing applications, it is definitely just one type of load testing using only one type of load generation; such equivalency is a serious conceptual mistake, dwarfing load testing and undermining performance engineering in general. LoadRunner) or Java (e.g.

Performance Testing 100

Performance Testing Technology Technology Testing 100

SQL Performance

APRIL 10, 2019

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. price ) AS bottomprice , LAST ( C. LAST ( C. price ) , C AS C. price > PREV ( C. price ) AS bottomprice , LAST ( C.

C++ 73

C++ Servers Virtualization Code 73

Smashing Magazine

NOVEMBER 26, 2021

checks for type definition during build time. Most front-end applications will fetch data from a back-end server and render it on the page. There is an excellent article The Testing Trophy and Testing Classifications by Kent C. In certain cases, the build will fail if there are type mismatches in your code as Next.js

Cache 143

Cache Code Testing Design 143

SQL Performance

AUGUST 12, 2020

You can find it in the documentation of Microsoft SQL Server and Azure SQL Database. T-SQL supports it starting with SQL Server 2005. Here the parser cannot tell whether the WITH clause is supposed to be used to define a table hint for the Customers table in the first statement, or start a CTE definition.

C++ 140

C++ Code Design Database 140

SQL Performance

DECEMBER 11, 2019

As a best practice, if you know that an attribute is not supposed to allow NULLs, make sure you enforce it with a NOT NULL constraint as part of the column definition. The documentation also states that support for this option will be removed in some future version of SQL Server. There are a couple of important reasons for this.

Best Practices 117

Best Practices C++ Database Code 117

SQL Performance

FEBRUARY 10, 2021

BatchMe ( col1 INT NOT NULL , INDEX idx_cs CLUSTERED COLUMNSTORE ) ; And here’s the code with the definition of the dbo.GetNumsAlanCharlieItzikBatch function: CREATE OR ALTER FUNCTION dbo. But this option is available only starting with SQL Server 2019, which introduced scalar UDF inlining. L0 AS ( SELECT 1 AS c.

C++ 124

C++ Servers Testing Code 124

SQL Performance

JANUARY 8, 2020

A much more elegant option is to use the CONCAT_WS function, which was introduced in SQL Server 2017. ( 1 , 'A' , 100.00 ) , ( 2 , 'B' , 200.00 ) , ( 3 , 'C' , NULL ) ; Notice that contacts 1 and 2 have applicable hourly rates, and contact 3 doesn't, so its hourly rate is set to NULL. 3 C NULL 4 D 150.00

Design 65

Design C++ Code Database 65

Smashing Magazine

JULY 18, 2022

If you think that static rendering is limited to generic, public content that is the same for every user of your website, you should definitely read this article. Segmented Rendering is a new pattern for the Jamstack that lets you personalize content statically, without any sort of client-side rendering or per-request Server-Side Rendering.

Cache 115

Cache Website Energy Servers 115

Percona

JULY 5, 2023

Checking server version. For example, you can’t dump and restore user definition: mysql 80 > show create user msandbox_ro@localhostG 1. For example, you can’t dump and restore user definition: mysql 80 > show create user msandbox_ro@localhostG 1. Any changes in system tables made since the 8.0

C++ 117

C++ Database Servers Testing 117

Percona

AUGUST 30, 2023

The most common parameter used by the PostgreSQL server (postmaster) will be PGDATA, which sets the parameter data_directory. Here is an example: $ export PGDATA=/home/postgres/data $ export PGPORT=5434 $ pg_ctl start waiting for server to start.2023-08-04 But changing this is possible only at the server startup.

Database 102

Database Servers Open Source Tuning 102

The Agile Manager

FEBRUARY 29, 2016

We used to want Master Story Lists to guide incremental development; today we want to iteratively experiment through code and have the feedback inform requirements definition and prioritization.

Government 40

Government Games C++ Virtualization 40

SQL Performance

NOVEMBER 11, 2020

WITH C AS ( SELECT SYSDATETIME ( ) AS dt ) SELECT @i += 1 FROM C WHERE dt = dt ; PRINT @i ; GO. -- Batch 3. WITH C AS ( SELECT SYSDATETIME ( ) AS dt ) SELECT @i += 1 WHERE ( SELECT dt FROM C ) = ( SELECT dt FROM C ) ; PRINT @i ; GO. ) SELECT C1. orderid , C1.

C++ 122

C++ Code Storage Processing 122

SQL Performance

APRIL 8, 2020

As Grant repeatedly points out, many who use common table expressions in T-SQL think that SQL Server persists the inner query result set, and that the reason for this belief is the use of the term table in the construct's name. When I read C. SQL guarantees that the columns will be returned from left-to-right based on definition order.

C++ 143

C++ Azure Database Servers 143

Percona

OCTOBER 17, 2023

The dynamic allocation might have flaws, but it’s definitely a good addition. Shard Key Analyzer helper – analyzeShardKey() The shard key is a critical component of your cluster, as it dictates the distribution of your data through the shards, and that’s where the problem lies. 7001 closed percona> exit /opt/mongo/6.0.6-5/bin/mongod

Metrics 101

Metrics C++ Storage Database 101

HammerDB

FEBRUARY 25, 2021

When we have multiple CPU cores on both the benchmark client and database server it is crucial that these database sessions run independently of each other at the same time, in parallel. For HammerDB both TPROC-C and TPROC-H run all of their workloads on the database being tested in SQL. Database interfaces in C. select top 100.

Programming 67

Programming Benchmarking Virtualization C++ 67

SQL Performance

APRIL 14, 2021

Here’s the function’s definition: -- Helper dummy table. BatchMe ( col1 INT NOT NULL , INDEX idx_cs CLUSTERED COLUMNSTORE ) ; GO. -- Function definition. b FROM L1 AS A CROSS JOIN L1 AS B CROSS JOIN L1 AS C ) INSERT INTO dbo. Here’s the function’s definition: CREATE OR ALTER FUNCTION dbo. BatchMe ; GO.

C++ 112

C++ Servers Testing Code 112

SQL Performance

MAY 12, 2021

And here’s the code with the function’s definition: CREATE OR ALTER FUNCTION dbo. Scan count 2, logical reads 0, physical reads 0, page server reads 0, read-ahead reads 0, page server read-ahead reads 0, lob logical reads 44 , lob physical reads 0, lob page server reads 0, lob read-ahead reads 0, lob page server read-ahead reads 0.

C++ 111

C++ Servers Database Code 111

SQL Performance

NOVEMBER 13, 2019

Never mind the likelihood for this to happen in practice in SQL Server; if I run the query again, theoretically, the row with id 2 could be assigned with row number 3 and the row with id 11 could be assigned with row number 2. Here's the definition of the POC that supports our query: CREATE INDEX idx_grp_data_i_id ON dbo.

Servers 104

Servers C++ Storage Performance 104

SQL Performance

MARCH 11, 2020

SQL Server handles NULLs just like non-NULL values for the purpose of enforcing a unique constraint. The standard unique constraint definition is a bit different than the T-SQL version. Suppose that you have a database in a platform that supports the standard unique constraint and you need to migrate that database to SQL Server.

C++ 135

C++ Code Servers Database 135

SQL Performance

MAY 8, 2019

GetNums ( 1 , 100 ) AS C WHERE C. If you haven’t figured it out yet, look closely at the definitions of both tables—specifically the column names—and at the column names used in the query. Since the reference to custid in the inner query is unqualified, SQL Server has to resolve which table the column is coming from.

Best Practices 68

Best Practices C++ Code Servers 68

Smashing Magazine

AUGUST 9, 2021

It was heralded as an amazing performance revolution, with exciting new features such as server push, parallel streams, and prioritization. We would have been able to stop bundling resources, stop sharding our resources across multiple servers, and heavily streamline the page-loading process. In older versions of TLS (say, version 1.2

Transportation 145

Transportation Internet Internet Network 145

Testsigma

FEBRUARY 3, 2021

Dynamic analysis : The applications are executed in real-time and tested for weak spots like authentication/authorisation issues, server issues, data transfer breaches. Example: Authentication process between client and server is processed through the request-response model. Recovery Testing.

Mobile 82

Mobile Testing Hardware C++ 82

Dotcom-Montior

MAY 26, 2020

Now let’s analyze that little deeper to understand this definition. . Let’s say there are three functions – a , b and c. Function c is getting called from b and b is getting called from a. It will also show that function c was called by function b , which in turn was called by function a.

Monitoring 54

Monitoring C++ Website Programming 54