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

Which `mysql>` command lists the databases defined and managed by the database server?


Which <code>mysql&gt;</code> command lists the databases defined and managed by the database server?

**(True or False)** Assuming that we have the `customers` table with `id` and `name` columns, the following two commands are equivalent:
 
```
1) select id, name from customers;
2) select * from customers;
```

(True or False) Assuming that we have the <code>customers</code> table with <code>id</code> and <code>name</code> columns, the following two commands are equivalent:
<pre><code>1) select id, name from customers;
2) select * from customers;
</code></pre>

It does nothing because it’s missing the `where` clause to specify which customers entries to delete.


 It deletes all entries from the `customers` table, but it first asks for confirmation.

It deletes all entries from the `customers` table without asking for any confirmation.

     

It asks for the `id` of each customer to delete and then deletes them.


What does the following command do?
  ```
  delete from customers;
  ``` 
     

What does the following command do?
<pre><code>delete from customers;
</code></pre>

Assume that we have a `customers` table with the following two entries:


  `{id: 1, name: 'John Woo'}`

  `{id: 2, name: 'Maria Foo'}`

 If the `id` is an integer that is auto-incremented by MySQL, what will the new customer `id` be when we run the command below?

 ```
delete from customers where name like '%oo';
```



Assume that we have a <code>customers</code> table with the following two entries:
<code>{id: 1, name: 'John Woo'}</code>
<code>{id: 2, name: 'Maria Foo'}</code>
If the <code>id</code> is an integer that is auto-incremented by MySQL, what will the new customer <code>id</code> be when we run the command below?
<pre><code>delete from customers where name like '%oo';
</code></pre>

```
select * from customers where name = 'John Woo' or name = 'Maria Foo';
```

```
delete from customers where name = 'John Woo';
```

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

```
select * from customers where name like '%pou%';
```

Given the `customers` table with the `name` column, which command brings the customers that have the `name` of`John Woo` or `Maria Foo`?


Given the <code>customers</code> table with the <code>name</code> column, which command brings the customers that have the <code>name</code> of<code>John Woo</code> or <code>Maria Foo</code>?

Test your understanding of SQL commands.


Getting Started

Manage MySQL Server

Basic SQL Commands

Add Columns and Indexes

Count and Sort Records

Foreign Keys

Joins, Left Joins And Subqueries

Conclusion

Quiz on SQL Queries