JIYIK CN >

Unlike SQL Server, PostgreSQL does not have a built-in DATEDIFF function to calculate the difference between dates. However, you can use expressions that include other functions provided by PostgreSQL to obtain the difference between dates....

In this tutorial, we will learn how to insert data from a database hosted on a remote server into a database in our local computer. We will use the remote service provider Heroku PostgreSQL, which offers a free plan for testing purposes. In...

PostgreSQL provides many functions and operators for built-in data types. This tutorial will give an example of extracting the date from a timestamp in PostgreSQL or Postgres. CAST Extracting the date from a timestamp using the operator in...

In this article, we will learn how DATEFIELD to find the day of the week from a given in the table in PostgreSQL. We will also learn about different operations that you can use to manipulate and work with DATEFIELD the data in . We use EXTR...

Before we begin, let's define what a timestamp is in SQL. From the PostgreSQL documentation under the DATE/TIME heading, a timestamp is a data type that stores a date and time in the following format. YYYY-MM-DD hh:mm:ss (DATE | TIME) The s...

with Statements are used to create temporary tables, which means that these tables are not persisted in the database and exist only in memory until the query is completed. The statement was introduced with to break down complex queries into...

The remote host uses the Linux system. The first step is definitely to establish a code synchronization mechanism on the local and remote hosts - sftp is the first choice. The second step is to write the CMakeLists.txt file of redis4. There...

clion mainly uses cmake + make for compilation. So for redis4, the main thing is to write the CMakeLists.txt file first. CmakeLists.txt file redis4/CMakeLists.txt cmake_minimum_required (VERSION 3.15 ) project (redis4) set (CMAKE_BUILD_TYPE...

In this article, we will introduce how to install redis under CentOS. In fact, the installation steps are very simple, but there may be some problems in the middle, which is worthy of our attention. Let's take a look at how to install it. F...

Redis has not made much optimization in terms of security, but has made great efforts in terms of performance and ease of use. A very simple security method for Redis is password verification, which requires the use of the AUTH command. Let...

To install apache2.4 in Windows 7, we first need to download the apache2.4 installation program. Here we download the software from the apache official website http://httpd.apache.org/download.cgi . First, let's see how to download apache2....

The split command, as a member of the pipeline command family, is used to split a large file into many small files. Sometimes, in order to improve readability, it is necessary to split a file into smaller fragments. Let's take a look at the...

The expand command converts the tab key into a space character. It is a member of the pipeline command family. Regarding expand, we will introduce an option -t NUM Convert the tab key to NUM spaces instead of the default 8 spaces. Same as c...

The function of the col command is to filter control characters. It is also a member of the pipeline command family. In many UNIX description files, there are RLF control characters. When we use the shell special characters "" and "" to out...

The join command is also a member of the pipeline command family. Its function is to connect the data of those rows with equal columns (that is, the first column) in each file. First we prepare two files /tmp/join1 and /tmp/join2. # cat /tm...