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.

testmysql.tar.gz

sql spa

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

We’ll do plenty of hands-on exercises on retrieving data stored inside our `customers` database. Before we proceed, let’s delete the existing data from our database. We’ll then insert data that will be useful later.

# Delete data from `order_items`, `orders`, and `customers`.
The following commands will delete all the data except the `products`. We’ll leave the `products` as they are:

```
mysql> delete from order_items;
Query OK, 2 rows affected (0.01 sec)

mysql> delete from orders;
Query OK, 2 rows affected (0.00 sec)

mysql> delete from customers;
Query OK, 2 rows affected (0.00 sec)
```

Let's verify these commands by executing them below:

Learn how to delete data from the 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

Delete Unnecessary Data

Delete data from `order_items`, `orders`, and

Delete Unnecessary Data

Delete data from order_items, orders, and

Delete data from `order_items`, `orders`, and