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


# The `like` operator
We’ll close this first chapter by learning about the `like` operator, which is very useful in `where` clauses.

Let’s look at an example. Assume that we know that the `name` of our customer ends with `Woo`, but we don’t remember the exact `name`. To search for customers whose `name` ends with `Woo`, we’ll use the following statement:


select * from customers where name like '%Woo';

Note that after running the above query, we get all the rows containing names that end with `Woo`.


``` shell
1 mysql> select * from customers where name like '%Woo';
2 +----+----------+
3 | id | name     |
4 +----+----------+
5 |  1 | John Woo |
6 +----+----------+
7 1 row in set (0.03 sec)
```

It returns one customer, the one whose `name` ends with `Woo`. The string format `%Woo` given to `like` tells the MySQL server to match the column value if it ends with `Woo`. The `%` means “anything.” So, `%Woo` means “anything to the left of `Woo`.”


Let’s look at another example. Assume that we know that the customer we’re looking for has a `name` that starts with `Maria`. In that case, we want the string to start with `Maria`, and we don’t care what follows. We’re going to indicate that by positioning the `%` to the right of `Maria`, like so:


Learn to extract specified data using the like operator in MySQL.


Retrieve Data Using the like Operator

Learn to extract specified data using the like operator in MySQL.

Getting Started

Manage MySQL Server

Basic SQL Commands

Add Columns and Indexes

Count and Sort Records

Foreign Keys

Joins, Left Joins And Subqueries

Conclusion

Retrieve Data Using the like Operator

The `like` operator

Retrieve Data Using the like Operator

The like operator

The `like` operator