Go through NULL

Many people know and use the built-in function ISNULL (X, Y), which replaces the first argument with the second argument if it is (first) NULL. Less useful is the inverse built-in function NULLIF (X, Y), which returns NULL if the first argument is equal to the second argument. The combination of these two functions avoids the use of IF-ELSE or CASE-WHEN constructions, which makes the code more compact. If it's interesting to see a couple of examples - welcome to the cat.
 
 
 
For example, here is the code that outputs 10 random integers in the range from 1 to 3? and the nearest value to the output ...
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Column DBMS versus lowercase, how about a compromise?

Column DBMS versus lowercase, how about a compromise?
 
Column DBMS actively developed in the zero years, at the moment they found ours and almost do not compete with traditional, lower-level systems. Under the cut, the author decides whether a universal solution is possible and how expedient it is.
 
Here ):
 
 
Commercial
 
 
 
1010data's Tenbase database
 
Alterian's Engine
 
Aster Data Systems
 
Calpont InfiniDB Enterprise Edition
 
EXASOL
 
...
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How to copy data sources to the IDE on the IntelliJ

How to copy data sources to the IDE on the IntelliJplatform.Hello! In this tutorial, consider a few popular scenarios.  - Copying the data source within a single project. - A common data source for different projects within the same IDE. - Copy the data source to another IDE, to another computer, to another galaxy.  export settings . But you do not always want to transfer all the settings, and the data sources - global ones, too, are not always :)  So it will be useful to know that the data source can be copied: on the shortcut menu, selectDatabase tools → Copy data source to clipboard. This will work with several at once.    The clipboard gets the ...
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Olympiad SQL: parsing the problem about the calendar

Olympiad SQL: parsing the problem about the calendar Hello, on the air of Radio SQL!
 
We continue the topic of popularizing the SQL language among the broad masses of the IT population of our planet, this time in the Russian-language part of it. However, the inhabitants of other planets, too, pull yourself up. Tune in to our gravity wave, smear mucus, straighten the shells and make yourself comfortable - we begin!
 
In this article, I'm going to parse the problem of the calendar that I gave on Olympics on SQL , about which I already wrote earlier. Exciting recursion and cryptic aggregate functions, nested queries and
armed with
grouping of data - ...
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[Перевод]Handling errors and transactions in SQL Server. Part 1. Error handling - quick start

Hello, Habr! I present to your attention the translation of article "Error and Transaction Handling in SQL Server. Part One - Jumpstart Error Handling » by Erland Sommarskog.
 
 

1. Introduction


 
This article is the first in a series of three articles devoted to error handling and transactions in SQL Server. Its goal is to give you a quick start in the topic of error handling, showing a basic example that fits most of your code. This part is written in reference to an inexperienced reader, and for this reason I deliberately keep silent about many details. At the moment, the task is to ...[/h]
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Introduction to Data Engineering. ETL, star schema and Airflow

Introduction to Data Engineering. ETL, star schema and AirflowThe ability of data scientist to extract value from data is closely related to the extent to which the infrastructure of data storage and processing in the company is developed. This means that the analyst should not only be able to build models, but also have sufficient skills in the field of data engineering, to meet the needs of the company and to undertake more and more ambitious projects.
 
 
However, despite all the importance, education in the field of data engineering continues to be very limited. I was lucky because I had time to work with many engineers who patiently explained to me every ...
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DevConf 2018 - voting for the reports

May 1? 2018 in Digital October (Moscow) will DevConf - a large annual conference for web developers, where they discuss all the newest in the world of programming for the web. The program is determined by voting for reports .
 
 
DevConf 2018 - voting for the reports
 
In section BackEnd : the future of PHP, thinking about aggregates, service-oriented architecture, little about blocking, the difficulties of rewriting the project, tracing, profiling, etc.
 
 
In section FrontEnd : React, GraphQL, Node.JS, WebRTC video calls, TVs, tests and developer PhantomJs.
 
 
In section ...
SQL / PHP
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Someone did not notice how MySQL 8.0 came out

Unexpectedly for myself, I found out that mysql suddenly released itself the other day (April 19), but there are no articles on the hub - everyone is discussing themselves-you know-what.
 
I'll try to translate the squeeze out of "What's new". For those who follow the development, there probably will not be anything or almost nothing new, for those interested in time-to-time - may seem interesting. Go tell that in the original post more detailed
 
the analysis of all the items - here only a short excerpt with references.
 
...
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What's new in DataGrip 2018.1

Hello! In this release, some improvements have appeared in minor updates. But, as we do not write about them on Habr, I'll tell in this post about everything new since the previous release.
 
 
What's new in DataGrip 2018.1
 
requested in the comments couple of releases back :)
 
 

 
 

Running the query


 

Read-only mode


 
We have the "Read-only" checkbox in the data source properties. It included this mode at the level of the jdbc-driver. But read-only is implemented in different drivers with the caveats:
 
- In SQLite It can not be switched for an already created connection.
 
- In MySQL it does not allow you to run queries that do not start with the "S" character.
 
- In Oracle, SQL Server and some other databases it does not work ...[/h][/h]
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