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This lesson covers the different options you have available to you for administering your MySQL service after it is successfully installed. If you already have that base covered feel free to skip on to the next lesson....

If you're storing anything in MySQL databases that you do not want to lose, chances are you should be doing weekly or even daily backups. Depending on what you're using your databases for -- be it to store forum...

Before you can do anything with MySQL in PHP you must first establish a connection to your web host's MySQL database. This is done with the MySQL connect function. mysql localhost If you've been around the internet a...

This lesson will teach you how to use the aggregate function COUNT(). If you missed the Aggregate Introduction Lesson, please check it out now, as it explains many concepts used in this lesson! We will be using the...

A MySQL table is completely different than the normal table that you eat dinner on. In MySQL and other database systems, the goal is to store information in an orderly fashion. The table gets this done by making the...

A MySQL database is nothing in itself. Rather a MySQL database is a way of organizing a group of tables. If you were going to create a bunch of different tables that shared a common theme, you would group them into one...

Maintenance is a very common task that is necessary for keeping MySQL tables current. From time to time, you may even need to delete items from your database. Some potential reasons for deleting a record from MySQL...

MySQL doesn't have a Fetch Array function. mysql_fetch_array is actually a PHP function that allows you to access data stored in the result returned from a successful mysql_query. If you have been jumping around our...

After you have mastered the basics of MySQL, it's time to take the next step and take on Aggregate Functions. Before we talk about what they are, let's review the definition of aggregate, as it relates to MySQL:...

When data is put into a MySQL table it is referred to as inserting data. When inserting data it is important to remember the exact names and types of the table's columns. If you try to place a 500 word essay into a...

MySQL is currently the most popular open source database server in existence. On top of that, it is very commonly used in conjunction with PHP scripts to create powerful and dynamic server-side applications. MySQL has...

Thus far we have only been getting data from one table at a time. This is fine for simple tasks, but in most real world MySQL usage you will often need to get data from multiple tables in a single query. The act of...

In the previous lesson, Mysql Joins we learned how to do a basic join of two tables. This lesson will teach you how to do a specialized join: left join. mysql left join explanation How is a LEFT JOIN different from a...

It would be nice to be able to make MySQL results easier to read and understand. A common way to do this in the real world is to order a big list of items by name or amount. The way to order your result in MySQL is to...

So far we have seen a couple different uses of PHP's mysql_query function and we'll be seeing more of it as nearly all MySQL in PHP is done through the MySQL Query function. We have already created a new table and...

If you have ever taken raw user input and inserted it into a MySQL database there's a chance that you have left yourself wide open for a security issue known as SQL Injection. This lesson will teach you how to help...

You have seen two types of MySQL queries thus far: the query which we used to create a table and the query we used to insert data into our newly created table. The query in this lesson is SELECT, which is used to get...

The easiest way to experiment with MySQL and PHP is to purchase some space on a shared web host. Although you can set up MySQL manually on your home PC, it can be rather difficult for a beginner to do, and would...

This lesson will teach you how to use the aggregate function SUM(). If you haven't already read through Tizag's Aggregate Introduction Lesson, please check it out now. It explains concepts used in this lesson. We will...

The great thing about everything you do in MySQL is that the "code" is very easy for humans to read, as opposed to harder programming languages like C or C++. Very few special characters and symbols are required to...

This tutorial outlines the steps for importing and exporting MySQL databases via command line (SSH). 1. Export A MySQL Database This example shows you how to export a database. It is a good idea to export your data...

Imagine that you have a MySQL table that holds the information of all the employees in your company. One of the columns in this table is called "Seniority" and it holds an integer value of how many months an employee...

In a previous lesson we did a SELECT query to get all the data from our "example" table. If we wanted to select only certain entries of our table, then we would use the keyword WHERE. WHERE lets you specify...

This lesson will teach you how to use the aggregate function AVG(). If you missed the Aggregate Introduction Lesson, please check it out now. It explains the meaning of aggregates and describes the GROUP BY statement....

MySQL comes with several data types for storing a date in its database system: DATETIME, DATE, TIMESTAMP, and YEAR. This lesson will show you the proper formats of each type, show their related MySQL functions, and give...

Hardware enthusiasts have been overclocking their PCs for years now, trying to push the limits of their hardware for maximum performance. Sometimes they are successful and their applications run speedy fast, while other...

This lesson will teach you how to use the MAX() aggregate function . If you missed the Aggregate Introduction Lesson, please check it out now, as it explains many concepts used in this lesson! You can download the...

This lesson will teach you how to use the aggregate function MIN(). If you missed the Aggregate Introduction Lesson, you might want to check it out to learn about the GROUP BY statement and its use with MySQL aggregate...

There are three different types of time data types in MySQL: TIME, DATETIME, and TIMESTAMP. If you would like to learn more about DATETIME and TIMESTAMP, then check out our MySQL Date section, as we've covered them...