WHAT IS RDBMS?

RDBMS stands for Relational Database Management System. RDBMS data is structured in database tables, fields and records. Each RDBMS table consists of database table rows. Each database table row consists of one or more database table fields. RDBMS store the data into collection of tables, which might be related by common fields (database table columns). … Read more

time_to_sec MySQL function

MySQL Function

time_to_sec MySQL function The TIME_TO_SEC() function converts a time value into seconds. SELECT TIME_TO_SEC(“19:30:10”); Output: 70210 SELECT TIME_TO_SEC(“-03:30:00”); Output: -12600 PHP MySQL Program example of time_to_sec <!doctype html> <html lang=”en”> <head> <meta charset=”utf-8″> <meta name=”viewport” content=”width=device-width, initial-scale=1″> <title>example-time_to_sec-function – php mysql examples | w3resource</title> <meta name=”description” content=”PHP MySQL PDO Example”> <link rel=”stylesheet” href=”https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css”> </head> <body> … Read more

Web Functionality

In addition to the core communications protocol used to send messages between client and server, web applications employ numerous different technologies to deliver their functionality. Any reasonably functional application may employ dozens of distinct technologies within its server and client components. Before you can mount a serious attack against a web application, you need a … Read more

How to Install LAMP Server on CentOS 8

LAMP, an acronym for Linux, Apache, MySQL, and PHP, is a popular free and open-source stack used by website administrators and developers alike to test and host dynamic websites. The LAMP server comes with 4 core components: the Apache web server, MySQL or MariaDB database and PHP which is a popular scripting language that is … Read more

mysql_secure_installation – MySQL Script

mysql-mysql_secure_installation

mysql_secure_installation – MySQL Script mysql_secure_installation is a shell script available on Unix systems, and enables you to improve the security of your MariaDB or MySQL installation in the following ways: You can set a password for root accounts. You can remove root accounts that are accessible from outside the local host. You can remove anonymous-user accounts. … Read more

MySQL Server Logs

mysql 5.7

 MySQL Server Logs MySQL Server has several logs that can help you find out what activity is taking place. By default, no logs are enabled, except the error log on Windows. (The DDL log is always created when required, and has no user-configurable options. The following logspecific sections provide information about the server options that … Read more

mysqld dead but subsys locked

mysql 5.7

mysqld dead but subsys locked Backup for future Safety: cp /var/lock/subsys/mysqld /root/mysqld than delete it rm /var/lock/subsys/mysqld then close all services that depends on mysql: service httpd stop and after that: service mysqld restart service httpd restart  

Rename database in MySQL

mysql 5.7

From phpMyAdmin, select the database you want to select. In the tabs there’s one called Operations, go to the rename section. That’s all. It does, as many suggested, create a new database with the new name, dump all tables of the old database into the new database and drop the old database. Other method: Create … Read more

get the difference between two timestamps in seconds

get the difference between two timestamps in seconds   You could use the TIMEDIFF() and the TIME_TO_SEC() functions as follows: SELECT TIME_TO_SEC(TIMEDIFF(‘2010-08-20 12:01:00’, ‘2010-08-20 12:00:00’)) diff; +——+ | diff | +——+ | 60 | +——+ 1 row in set (0.00 sec) You could also use the UNIX_TIMESTAMP() function. SELECT UNIX_TIMESTAMP(‘2010-08-20 12:01:00’) – UNIX_TIMESTAMP(‘2010-08-20 12:00:00’) diff; +——+ | diff | +——+ | … Read more

mysql length function : calculate length of a column

mysql 5.7

mysql length function : calculate length of a column Function length() Return the length of the string Usages SELECT CustomerName, LENGTH(CustomerName) AS LengthOfName FROM Customers; Tablenames Records Customers 91 Categories 8 Employees 9 OrderDetails 2155 Orders 830 Products 77 Shippers 3 Suppliers 29