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

Before we do anything else, let’s see our `customers` table:


# Use of `current_timestamp` with `insert`
Now, we’re going to insert a new order in the `orders` table. We’ll use the following command:

```
insert into orders (order_number, ordered_at, customer_id) values ('ABC001', current_timestamp, 1);
```


Before we actually execute this command, let’s look at the new stuff here. Specifically, lets take a look at `current_timestamp`. This is used as a value for the `ordered_at` column. It’ll ask MySQL to set the current date and time stamp so we don’t have to specify any precise date and time ourselves.

Also, notice the number value `1` for the `customer_id`. This is the id of the customer the new order is going to be linked to. In other words, we want the new order created to be owned by the customer with `id 1`, which is the customer `John Woo`.

We’re using the integer numbers in the `id` field to reference a `customers` entry from an entry inside the `orders` table. The integer values of the customer `id` are stored inside the `customer_id` column of the `orders` table. That is why the type of the `customer_id` column is the same as the type of the `id` column on the `customers` table (they are both `int(11)`).

Now, let’s execute the command and `select` statement to retrieve and verify the data has been inserted:


Learn to insert data into the orders 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

Insert Data into the orders Table

Use of `current_timestamp` with `insert`

Insert Data into the orders Table

Use of current_timestamp with insert

Use of `current_timestamp` with `insert`