Gain insights into relational databases and SQL. Learn about creating, managing, and editing tables using MySQL. Explore complex queries, indexes, and join functions for efficient data handling.

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Relational databases store data in a row-based table structure. Structured Query Language (SQL) is a core language used to retrieve data from the relational database. One of its most widely used extensions, MySQL, also gives you the power to edit, create, and manage the queried data.

In this course, you’ll be introduced to the basics of relational database management with SQL. You’ll use MySQL to create a table, edit the data, and even change the structure. You’ll also create indexes to quickly access data for faster performance on common queries. Additionally, you’ll explore more complex queries to extract useful data with aggregate functions, grouping, ordering, and creating limits and filters in output tables. Finally, you’ll learn how to combine data from different tables with join functions.

By the end of this course, you’ll be able to create, manage, edit, and merge relational databases with confidence. MySQL will prepare you for data projects large and small.

Getting Started with SQL and Relational Databases

So far, we’ve become familiar with different queries like `insert`, `delete`, `update`, and `select`. We’ve also used several operators for our different requirements. Now, we’ll learn to add a new column to an existing table. Let’s suppose that we want to introduce a column with the name `identity`. We assume that each customer has a unique identity number, and we want to introduce this concept to our data model.

# The `alter` table command

We execute the following `alter table` command to add the column:

``` shell
alter table customers add column(identity varchar(32) not null);
```

Before we actually execute that command, let’s explore the elements that are used to compose the command.

# Parts of the `alter table` command


Learn to add a new column to an existing table.

Getting Started

Manage MySQL Server

Basic SQL Commands

Add Columns and Indexes

Count and Sort Records

Foreign Keys

Joins, Left Joins And Subqueries

Conclusion

Add a New Column

The `alter` table command

Add a New Column

The alter table command

The `alter` table command