Database creation and selection in MySQL - Step-by-Step Execution

Concept Flow - Database creation and selection

Start

↓

Write CREATE DATABASE statement

↓

Execute CREATE DATABASE

↓

Database created?

No→Error: Fix and retry

Yes↓

Write USE statement

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Execute USE statement

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Database selected

↓

Ready for further commands

First, create a new database with CREATE DATABASE. Then select it with USE to work inside it.

Execution Sample

MySQL

CREATE DATABASE school;
USE school;

This code creates a database named 'school' and then selects it for use.

Execution Table

Step	SQL Command	Action	Result	Notes
1	CREATE DATABASE school;	Create database named 'school'	Success	Database 'school' created
2	USE school;	Select database 'school' for use	Success	Current database set to 'school'
3		Ready for next commands	N/A	Database 'school' is active

💡 Database 'school' created and selected successfully, ready for further commands.

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
Current Database	None	None	school	school

Key Moments - 2 Insights

Why do we need to run USE after CREATE DATABASE?

CREATE DATABASE only makes the database but does not select it. USE sets the current database to run commands inside it, as shown in execution_table step 2.

What happens if we try to create a database that already exists?

The CREATE DATABASE command will fail with an error. You must fix the name or drop the existing database first. This is implied in the flow where creation success is checked.

Visual Quiz - 3 Questions

Look at the execution table, what is the current database after step 1?

A mysql

B school

C None

D test

💡 Hint

Check the 'Current Database' variable in variable_tracker after step 1.

At which step does the database become selected for use?

A Step 2

B Step 1

C Step 3

D Before Step 1

💡 Hint

Look at the 'Action' and 'Result' columns in execution_table for step 2.

If the CREATE DATABASE command fails, what should you do next?

A Run USE command anyway

B Fix the error and retry CREATE DATABASE

C Drop the database and then run USE

D Nothing, the database is created automatically

💡 Hint

Refer to the concept_flow where failure leads to 'Error: Fix and retry'.

Concept Snapshot

CREATE DATABASE db_name;  -- creates a new database
USE db_name;              -- selects the database to work in
CREATE DATABASE only makes the database,
USE sets it as current for commands.
Always run USE after creating to select.

Full Transcript

To create and select a database in MySQL, first run CREATE DATABASE with your chosen name. This command makes the database but does not select it. Next, run USE with the database name to select it for your session. After USE, all commands run inside that database. If CREATE DATABASE fails, fix the error before continuing. This process ensures you have a database ready and selected for your work.