Database creation and selection in MySQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the SQL command to create a new database named 'library'?

The command is CREATE DATABASE library;. This creates a new empty database called 'library'.

beginner

How do you select a database named 'library' to use it for your queries?

Use the command USE library;. This tells the system to work with the 'library' database for following commands.

intermediate

What happens if you try to create a database that already exists without using any extra options?

You will get an error saying the database already exists. To avoid this, use CREATE DATABASE IF NOT EXISTS database_name;.

beginner

Why is it important to select a database before running queries?

Selecting a database tells the system where to look for tables and data. Without selecting, queries may fail or run on the wrong database.

beginner

Write the SQL commands to create a database named 'school' and then select it for use.

First, create the database: CREATE DATABASE school;<br>Then select it: USE school;

Which SQL command creates a new database?

A CREATE DATABASE database_name;

B SELECT DATABASE database_name;

C USE database_name;

D DROP DATABASE database_name;

The CREATE DATABASE command is used to create a new database.

How do you tell MySQL to use a specific database for your queries?

A USE database_name;

B CREATE DATABASE database_name;

C SELECT * FROM database_name;

D DROP DATABASE database_name;

The USE command selects the database for your session.

What will happen if you run CREATE DATABASE test; when 'test' already exists?

A It will overwrite the existing database.

B It will create a new database with a different name.

C It will give an error.

D It will delete the existing database.

Trying to create a database that exists causes an error unless you use IF NOT EXISTS.

Which command prevents an error if the database already exists when creating it?

A DROP DATABASE database_name;

B CREATE DATABASE database_name;

C USE database_name;

D CREATE DATABASE IF NOT EXISTS database_name;

Adding IF NOT EXISTS avoids errors if the database exists.

Why do you need to select a database before running queries?

A To delete the database.

B To tell MySQL which database to work with.

C To create a new database.

D To backup the database.

Selecting a database tells MySQL where to find tables and data for your queries.

Explain how to create a new database and select it for use in MySQL.

Think about the two steps: making the database and then telling MySQL to use it.

What is the purpose of the 'IF NOT EXISTS' clause in database creation?

It helps avoid errors when the database is already there.