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This tutorial will guide you through creating a MySQL EVENT timer, also known as a MySQL timer. We will see how to set a timer in MySQL to let MySQL manipulate the data (eg. UPDATE // data) INSERT . DELETE It will also take a backup (if req...

mysqld Is a daemon server program, also known as MySQL server. It is used to manage the MySQL data directory with tables and databases. This tutorial guides you through the various methods you can use to start, stop, or restart a MySQL serv...

This tutorial discusses how to check for duplicates in a MySQL table and retrieve the number of duplicates using the SELECT DISTINCT and statements, respectively. SELECT COUNT SELECT DISTINCT Check for duplicates in a MySQL table using The...

Traditional SQL INSERT statements do not perform input validation of their parameters/values ​​against existing database tables, which sometimes results in errors when duplicate keys are found during the insert process. This is handled...

This tutorial aims to understand unsigned in MySQL. unsigned Using keywords in MySQL Businesses and organizations have to assign data type as unsigned for certain columns. However, it is important to understand when and where to use this da...

Summary: in this tutorial, we will learn how to shuffle or sort the values ​​or records of a table in MySQL. Most businesses and organizations that use MySQL for data analysis or visualization need to sort different table values ​​o...

In this tutorial article, we will explain how to declare variables in SQL code for MySQL database. In SQL scripts, you can use variables to store values ​​and use them in place of literals during the execution of a series of commands. U...

Getting the distinct values ​​in a field is an important query. This article discusses how to get the distinct count of values ​​in a field. Get distinct count of field values ​​in PostgreSQL Consider a quiz_score table that rec...

This tutorial discusses how to convert an integer to a string in PostgreSQL. Convert integer to string in PostgreSQL Consider a quiz_score table that records the score of each participant in a quiz game. The scores are stored in this table...

This article discusses how to escape single quotes in PostgreSQL queries. Escaping single quotes in PostgreSQL Consider a comment table that records user comments. The table has 5 fields: id , userid , postid , comments , commentdate , as s...

The sort command is a commonly used sorting command in Linux , and it is also a pipeline command . In order to ensure that future instances can get the sorting results we want, we need to set the following # export LC_ALL=C Okay, next we wi...

The wc command is a commonly used command in Linux system, and it is also a member of the pipeline command family. wc is a statistical command, which is very simple to use and does not have as many options as sort. Let's take a look at the...

This article follows up on Linux extraction command grep (I) and Linux extraction command grep (II) and continues to introduce the options of the grep command and its usage. Option 3 -i is case insensitive to the search string $ grep Mail /...

This article follows up on Linux extraction command grep (Part 1) and continues to introduce the options and usage of the grep command. Option 2 In this group, we mainly introduce options to control grep output information. -m stops outputt...

Grep is a frequently used command in Linux. Like the cut command, it is a member of the pipeline command. Its function is to analyze a line of data and extract the data we want from the analyzed data. It is equivalent to a search function....