SQL Performance

MAY 13, 2020

I just wanted to mention some use cases here to illustrate how important table expressions are in our T-SQL code, and why it's worthwhile to invest in understanding their fundamentals well. Here's the standard's definition for derived tables in the general sense: 4.15.3 C is what's known as a range variable. Derived tables.

C++ 143

C++ Code Design Servers 143

SQL Performance

JANUARY 13, 2021

Here’s the code to create the dummy table: CREATE TABLE dbo. BatchMe ( col1 INT NOT NULL , INDEX idx_cs CLUSTERED COLUMNSTORE ) ; And here’s the code defining the dbo.GetNumsItzikBatch function: CREATE OR ALTER FUNCTION dbo. L0 AS ( SELECT 1 AS c. Here’s the function’s definition: CREATE OR ALTER FUNCTION dbo.

C++ 113

C++ Code Testing Processing 113

Percona

DECEMBER 29, 2022

for lib in $(psql -qtA pgbench -c"select extname||'.so' for lib in $(psql -qtA pgbench -c"select extname||'.so' Also, you will see a section with the explicit creation of the C language functions for the extensions. A custom C function is using it. For example, with the following bash snippet.

C++ 81

C++ Open Source Database Programming 81

SQL Performance

DECEMBER 9, 2020

Use the following code to run a test with base CTE cardinality of 2 (requires 5 additional levels of CTEs): DECLARE @low AS BIGINT = 1 , @high AS BIGINT = 100000000 ; WITH. Make sure that you enable Discard results after execution in your SSMS Query Options dialog under Grid, Results.

C++ 114

C++ Servers Testing Processing 114

SQL Performance

JULY 13, 2022

This could also happen if you need to migrate code written for another database platform with a different dialect of SQL to T-SQL. Use the following code to create the Orders table and populate it with a small set of sample data to help you verify the validity of the solutions: SET NOCOUNT ON ; USE tempdb ; DROP TABLE IF EXISTS dbo.

C++ 112

C++ Code Azure Database 112

SQL Performance

MARCH 10, 2021

Here’s the code to create the dummy table: DROP TABLE IF EXISTS dbo. 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. BatchMe ; GO. CREATE TABLE dbo. BatchMe ON 1 = 0. and dbo.T3

C++ 134

C++ Testing Code Servers 134

Scalegrid

FEBRUARY 15, 2024

MongoDB® SSL with Self-Signed Certificates in C# Configuring MongoDB Server for SSL/TLS Encryption Once your certificates are ready, the next step is configuring the MongoDB server for SSL/TLS encryption, allowing you to securely connect to MongoDB. While we’re yet to run comprehensive tests, there is definite overhead due to using SSL.

Servers 130

Servers Best Practices Government Network 130

SQL Performance

APRIL 13, 2022

Use the following code to create a table called T1 and populate it with a small set of sample data: SET NOCOUNT ON ; USE tempdb ; DROP TABLE IF EXISTS dbo. 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.

C++ 136

C++ Strategy Testing Servers 136

Dynatrace

NOVEMBER 8, 2021

G2 Research includes a clear definition of APM in its Grid Report for Application Performance Monitoring for Spring 2021. The right APM tool will also help you keep a close eye on application transactions along with their business context and code-level detail. ” — Christopher C, Platform Manager at an enterprise.

Artificial Intelligence 233

Artificial Intelligence Monitoring Infrastructure Cloud 233

The Morning Paper

NOVEMBER 12, 2019

Scaling symbolic evaluation for automated verification of systems code with Serval Nelson et al., Here are the resulting code and specification sizes, together with the verification runtimes (impressively short!). SOSP’19. Serval is a framework for developing automated verifiers of systems software. Symbolic evaluation primer.

Code 45

Code Systems Programming Google 45

SQL Performance

JULY 27, 2021

As well as the nonclustered index correctness checks, if there’s a persisted computed column in the definition of a table, then for each data record in the table, DBCC CHECKDB has to check that the persisted value is correct, regardless of whether that column is part of a nonclustered index or not. columns [ c ] JOIN sys.

C++ 54

C++ Servers Database Code 54

Sutter's Mill

JUNE 3, 2021

Briefly, what is the difference among: (a) undefined behavior Undefined behavior is what happens when your program tries to do something whose meaning is not defined at all in the C++ standard language or library (illegal code and/or data). By definition, if a function’s preconditions are violated, then the results are not specified.

C++ 54

C++ Programming Lambda Code 54

Sutter's Mill

JANUARY 11, 2021

Assertions have been a foundational tool for writing understandable computer code since we could write computer code… far older than C’s assert() macro, they go back to at least John von Neumann and Herman Goldstine (1947) and Alan Turing (1949). 1,2] How well do we understand them… exactly? GUIDELINE: Assert liberally. [3]

C++ 58

C++ Programming Code Testing 58

SQL Performance

DECEMBER 9, 2020

Use the following code to run a test with base CTE cardinality of 2 (requires 5 additional levels of CTEs): DECLARE @low AS BIGINT = 1 , @high AS BIGINT = 100000000 ; WITH. Make sure that you enable Discard results after execution in your SSMS Query Options dialog under Grid, Results.

C++ 61

C++ Servers Testing Processing 61

Adrian Cockcroft

FEBRUARY 9, 2023

The third is that the Team Topologies book defined how to create and manage Platform Teams so there’s interest in the terminology and definition. We wanted AWS to grow its platform functionality, and to continually eat away at the bottom of the thin layer of rapidly evolving Netflix specific platform code that we had built.

Engineering 137

Engineering Serverless Lambda AWS 137

The Netflix TechBlog

MARCH 2, 2021

David Cameron (Studio Production) [David C.] My academic credentials definitely helped on the technical side. Coding with statistical software and SQL are my most widely used technical skills. What best prepared you for your current role at Netflix? Aliki Mavromoustaki (Content & Marketing) [Aliki M.]

Analytics 207

Analytics C++ Innovation Engineering 207

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. You can download the source code to create and populate this database here. The following query, which I’ll refer to as Query 5, illustrates this technique: WITH C AS. ( Environment for Demos.

C++ 133

C++ Database Servers Code 133

SQL Performance

OCTOBER 1, 2020

In my last post , I showed how to use TSqlParser and TSqlFragmentVisitor to extract important information from a T-SQL script containing stored procedure definitions. And with the Visitor code I provided, the output to the console was: ==. Param name: @c. AS PRINT 1 ; GO. ProcedureReference. ==. dbo.procedure1. ==. Default: -64.

C++ 57

C++ Code Database Systems 57

CSS Wizardry

JULY 21, 2018

le|c|sa|sc)ss$/{print}' | nl. This very non-scientific method of checking code usage should give you an approximate idea of what might be dead code, or what you might simply be able to ignore. For a slightly more robust, but still imperfect method of identifying dead code, try this technique that I wrote up earlier in 2018.

Programming 142

Programming C++ Database Code 142

Smashing Magazine

NOVEMBER 26, 2021

However, there are a few ways in which you can make a large code-base easy to maintain. In certain cases, the build will fail if there are type mismatches in your code as Next.js checks for type definition during build time. We recommend using code editor type checking during development.”. applications. From the Next.js

Cache 143

Cache Code Testing Design 143

SQL Performance

JUNE 10, 2020

That is, does SQL Server perform a substitution process whereby it converts the original nested code into one query that goes directly against the base tables? Recall that a relation’s body—being a set of tuples—by definition has no duplicates. Unnesting/substitution/inlining: Does SQL Server unnest, or inline, the derived table query?

C++ 109

C++ Database Servers Code 109

Sutter's Mill

FEBRUARY 25, 2021

Explain your answer using the following example, which uses a variation of a proposed post-C++20 syntax for preconditions. [1] GUIDELINE: Use a precondition to write “this is what a bug is” as code the caller can check. A precondition states in code the circumstances under which this function’s behavior is not documented.

C++ 49

C++ Code Testing Systems 49

Particular Software

AUGUST 30, 2021

Do you hate boilerplate code? Have you heard of C# source generators 1 and thought they sounded pretty cool but didn’t really know how they could be useful? Now, this code is all it takes to write transactionally consistent NServiceBus handlers inside of your Azure Function project. Do you think Azure Functions are pretty great?

Azure 52

Azure Transportation C++ Code 52

SQL Performance

JUNE 10, 2020

That is, does SQL Server perform a substitution process whereby it converts the original nested code into one query that goes directly against the base tables? Recall that a relation’s body—being a set of tuples—by definition has no duplicates. Unnesting/substitution/inlining: Does SQL Server unnest, or inline, the derived table query?

C++ 93

C++ Database Servers Code 93

The Morning Paper

MAY 16, 2019

bugs you do let slip into your code. The six applications studied were Docker, Kubernetes, etcd, CockroachDB, gRPC, and BoltDB, so that’s a lot of important real-world Go-code right there. An especially interesting comparison can be made in the case of gRPC, which has both a C implementation and a Go implementation.

Programming 100

Programming C++ Design Code 100

SQL Performance

AUGUST 2, 2019

There are a few additional coding recommendations that Pam Lahoud discusses in her very informative post, TEMPDB – Files and Trace Flags and Updates, Oh My! I restored a copy of WideWorldImporters and then created three stored procedures (definitions below). OrderID , c. Customers c ON o. CustomerID = c.

Servers 95

Servers C++ Testing Systems 95

DZone

FEBRUARY 27, 2021

The legacy languages — be it ASM or C still rule in terms of performance. But these are definitely ruled out for enterprise applications due to the complexity in development, maintainability, need for object orientation, and interoperability. C++ SOLUTION (Will Be Uploaded Later). These include Python, PHP, Perl, and Ruby.

Java 207

Java C++ Benchmarking Programming 207

Nick Desaulniers

MAY 12, 2019

Prefer f(void) in C to potentially save a 1B instruction per function call when targeting x86_64 as a micro-optimization. Doesn’t matter for C++. While messing around with some C code in godbolt Compiler Explorer , I kept noticing a particular funny case. For example, the following C code: 1. The Problem.

C++ 111

C++ Code Testing 111

Randon ASCII

MARCH 30, 2020

I did my tests on an October 2019 version of Chromium’s code because that gave me the most flexibility about which build options to use. The graph below shows the relationship between the number of lines of code in source files and how long it took to compile them. million lines of source code in the primary source files.

C++ 87

C++ Code Open Source Programming 87

CSS Wizardry

APRIL 25, 2019

I don’t think this article is definitive or gospel. The Head of Tech likely reports into C-level staff, so they’ll sit pretty close to the business, but might not have as much hands-on technical knowledge as a day-to-day engineer. Research the team’s stack, and prepare to shoot the sh*t about coding from the trenches.

Code 197

Code Engineering Design C++ 197

Sutter's Mill

JANUARY 25, 2021

We want a way to enable checking for some assertions but not others in the same code, because we may not always be able to afford expensive checks. If we could write all ideal assertions, and exercise all control flow and data flow during testing, then a failed assertion would definitely mean a bug in the same function where it was written.

C++ 45

C++ Programming Cache Testing 45

All Things Distributed

DECEMBER 1, 2016

AWS Codebuild : A new, fully managed, extensible service for compiling source code and running unit tests, which is integrated with other application lifecycle management services— such as AWS CodeDeploy, AWS CodeCommit, and AWS CodePipeline— for dramatically decreasing the time between iterations of software.

AWS 163

AWS Development Lambda Open Source 163

Randon ASCII

JANUARY 22, 2017

In this episode I’ll show how deleting an inline function definition can lead to similar savings. The savings this time are less important as they are mostly in the.BSS segment, but there are also some modest code-size savings, and some interesting lessons. The definition of log2 and log2f in MathExtras.h Are you sure?

C++ 56

C++ Code Systems Processing 56

Sutter's Mill

MARCH 25, 2021

This is more obvious when the precondition involves multiple parameters (or ordinary variables for that matter); a poster child is the STL’s pervasive use of iterator pairs, which have long been crying out to be encapsulated using a range abstraction, and fortunately we now have that in C++20. Consider using a class instead. is_reachable?

C++ 45

C++ Design Code Systems 45

Percona

MARCH 7, 2019

In other words, the time the CPU was executing user code, such as MySQL. There could be more, but this particular query was definitely hurting the performance of the server. c) From there you can divert into the areas that are related to that resource and start to narrow down the issue. d) Tackle the problems bit by bit.

C++ 100

C++ Traffic Servers Monitoring 100

SQL Performance

APRIL 10, 2019

Use the following code to create the table, populate it with some sample data, and query it: SET NOCOUNT ON ; USE tempdb ; DROP TABLE IF EXISTS dbo. . ( Ticker ; This code generates the following output: symbol tradedate price -. price ) AS bottomprice , LAST ( C. LAST ( C. price ) , C AS C.

C++ 73

C++ Virtualization Servers Code 73

SQL Performance

AUGUST 12, 2020

What’s different about the design of CTEs compared to derived tables is where in the code these three elements are located. However, there are very few cases in T-SQL where without a terminator the code is ambiguous. The elements are sort of intertwined. In those cases, the termination is mandatory. Incorrect syntax near 'UC'.

C++ 140

C++ Code Design Database 140