ASAmol Shukla

2. Install MySQL and connect

Step 1 of 4 · Lesson

Lesson 2 of 21

How to install MySQL 8.4 and Workbench and run your first query

Install MySQL Community Server and Workbench on Windows, macOS or Linux, connect on port 3306, and fix the three most common connection errors.

80 min 5 min read 19 problems · 0 solved No tables needed

In short

How do I install MySQL and run my first query?

Download MySQL Community Server 8.4 (LTS) and MySQL Workbench from dev.mysql.com, run the installer, set a root password, and keep the server running. In Workbench create a connection to host 127.0.0.1, port 3306, user root, then open a SQL tab and run SELECT VERSION();.

By the end of this lesson you can

  • Install MySQL Community Server 8.4 and MySQL Workbench on your operating system
  • Create and test a Workbench connection (host, port, user)
  • Run SELECT VERSION() and other server checks
  • Diagnose 'connection refused', 'access denied' and 'no database selected'

What you are installing

You need two pieces of software:

  • MySQL Community Server — the database itself. It must be running for anything to work. Choose 8.4 LTS (long-term support). Any version from 8.0.16 works for this course; older 8.0 releases ignore CHECK constraints, which lesson 12 uses.
  • MySQL Workbench — the editor where you type SQL and see results.

Installing only Workbench is the most common beginner mistake: the editor opens, but there is no server to connect to.

Both are free from the official download page, dev.mysql.com/downloads. Pick the Community editions.

Install step by step

Follow the tab for your operating system. Keep the password you choose somewhere private — you need it every time you connect.

  1. Download MySQL Installer for Windows (the larger, full package) from dev.mysql.com/downloads/installer.
  2. Run it and choose Custom (or Developer Default). Select MySQL Server 8.4 and MySQL Workbench.
  3. Keep Config Type: Development Computer, Port 3306, and Use Strong Password Encryption.
  4. Set a root password. Optionally add a second user for daily practice.
  5. Keep Configure MySQL Server as a Windows Service and Start at System Startup ticked, so the server runs automatically.
  6. Finish, then open MySQL Workbench from the Start menu.

Connect from MySQL Workbench

  1. On the Workbench home screen, click + next to MySQL Connections.
  2. Connection Name: Local practice. Hostname: 127.0.0.1. Port: 3306. Username: root (or your practice user).
  3. Click Test Connection and enter the password. You should see Successfully made the MySQL connection.
  4. Click OK, then click the new tile to open it. A SQL editor tab opens.
  5. Type a query and press the lightning bolt (Execute) or Ctrl + Enter (⌘ + Return on a Mac) to run the statement under the cursor.

Results appear in the Result Grid below the editor. Errors appear in the Output panel at the bottom — always read that panel when something seems to do nothing.

Check the server you are connected to

These read-only checks are the first thing a professional runs on an unfamiliar server. They work before any database is imported:

SQL · no tables
SELECT VERSION() AS version, CURRENT_USER() AS user_name, @@port AS port, DATABASE() AS selected_db;
MySQL result1 row
versionuser_nameportselected_db
8.0.46-0ubuntu0.24.04.4root@localhost3306NULL

DATABASE() returns NULL until you choose a database with USE — that is normal, not an error. On your own server the version will say something like 8.4.x and the user will be root@localhost.

Troubleshooting the three most common errors

Message What it means Fix
Can't connect to MySQL server on '127.0.0.1:3306' (10061 / 2003) — connection refused No server is listening there: it is stopped, or the host/port is wrong Start the service (Windows Services → MySQL84, macOS System Settings → MySQL, Linux sudo systemctl start mysql). Check the port in the installer.
Access denied for user 'root'@'localhost' (1045) The server is running but the user name or password is wrong Re-type the password; check Caps Lock; on Ubuntu create a separate user as shown above.
No database selected (1046) You ran a query that needs a table before choosing a database Run USE portfolio_retail_lab; or double-click the database in the Schemas panel.
You have an error in your SQL syntax (1064) A typo, a missing comma or a missing quote Read the text after near — the mistake is just before it.

Save a connection-check script

Create a file called 00-connection-check.sql and keep it in your course folder. Running it at the start of each session proves that the server is up and tells you where you are:

SQL · no tables
SELECT 1 AS connection_ok;
SELECT VERSION() AS version, NOW() AS checked_at;
MySQL result 11 row
connection_ok
1
MySQL result 21 row
versionchecked_at
8.0.46-0ubuntu0.24.04.42026-11-01 19:15:05

Each statement produces its own result tab in Workbench. In the practice editor they appear one under the other.

Common mistakes

Wrong

Installing only MySQL Workbench

Fix

Install MySQL Community Server too and make sure its service is running.

Why: Workbench is just an editor. Without MySQL Server running there is nothing to connect to (error 2003).

Wrong

Running SELECT * FROM customers; straight after connecting

Fix

USE portfolio_retail_lab; first, after importing it in lesson 3.

Why: No database is selected yet, so MySQL does not know where the table is (error 1046).

Wrong

Pressing the plain lightning bolt with several statements and reading only the last tab

Fix

Use Ctrl + Enter to run just the statement under the cursor while learning.

Why: Execute runs every statement; each gives its own result tab.

Check yourself

  1. What is the difference between MySQL Server and MySQL Workbench?
  2. What does 'connection refused' tell you, compared with 'access denied'?
  3. Why does DATABASE() return NULL right after you connect?

Answer out loud or in your notebook. If one is hard, reread that section before practising.

Frequently asked questions

Which MySQL version should I install in 2026?

MySQL 8.4 LTS. Any 8.0.16 or newer release works for this course; versions before 8.0.16 silently ignore CHECK constraints.

What is the default MySQL port?

3306. Only change it if another program already uses that port, and then use the same port in your Workbench connection.

Can I learn MySQL without installing it?

Yes, to start. Every lesson here has a browser practice editor with the course database built in. Install MySQL later to learn the real tool employers use.

Quick quiz — 4 questions

Quick Check: Install MySQL and connect

1 / 4
Workbench opens but says it cannot connect to 127.0.0.1:3306. What is the most likely cause?

Answers — Install MySQL and connect

  1. Easy. Test your connection with SELECT 1. Target: The result grid contains 1, not a connection error.

    SELECT 1;

  2. Medium. Check which server you connected to. Target: Record your version locally; it must be MySQL 8.0+. Do not publish credentials.

    SELECT VERSION() AS mysql_version;

  3. Hard. Check whether a database is selected. Target: DATABASE() returns NULL before selecting a schema, or the selected schema name. NULL here is not a connection failure.

    SELECT DATABASE() AS selected_database;

  4. Professional. Save a safe connection-check script for your next session. Target: A saved .sql file contains only checks, no password or private connection string; both statements run after reconnecting.

    SELECT 1 AS connection_ok;
SELECT VERSION() AS mysql_version;

  5. Easy. Run SELECT 1 + 1 to prove the editor runs queries. Target: 1 row: two = 2

    SELECT 1 + 1 AS two;

  6. Easy. Show today's date from the server. Target: 1 row with today's date

    SELECT CURDATE() AS today;

  7. Easy. Show the current date and time. Target: 1 row with date and time

    SELECT NOW() AS right_now;

  8. Easy. Show which MySQL user you are logged in as. Target: 1 row like you@localhost

    SELECT CURRENT_USER() AS me;

  9. Medium. List all databases on the server. Target: Includes mysql, information_schema, sys

    SHOW DATABASES;

  10. Medium. Show which port the server listens on. Target: Usually 3306

    SELECT @@port AS port;

  11. Medium. Show the server version and edition in one row. Target: 8.0.16+ and Community Server

    SELECT VERSION() AS version, @@version_comment AS edition;

  12. Medium. Show the server's time zone settings. Target: Often SYSTEM, SYSTEM

    SELECT @@global.time_zone AS global_tz, @@session.time_zone AS session_tz;

  13. Medium. Check whether ONLY_FULL_GROUP_BY is on (you need it in lesson 5). Target: Text contains ONLY_FULL_GROUP_BY

    SELECT @@sql_mode;

  14. Hard. Run SELEC 1; on purpose and copy the error number. Target: Error 1064 (syntax error)

    SELEC 1;

  15. Hard. Run SELECT * FROM customers; before choosing a database. Target: Error 1046: No database selected

    SELECT * FROM customers;

  16. Hard. Run two statements in one go and see both result tabs. Target: Two result tabs: 1 and 2

    SELECT 1 AS first; SELECT 2 AS second;

  17. Hard. Show the character set of your connection. Target: utf8mb4 on MySQL 8

    SELECT @@character_set_client AS charset;

  18. Professional. Write a setup checklist script: version, user, port, sql_mode, selected database — five columns, one row. Target: 1 row, 5 columns; selected_db is NULL

    SELECT VERSION() AS version, CURRENT_USER() AS user_name, @@port AS port, @@sql_mode AS sql_mode, DATABASE() AS selected_db;

  19. Professional. Write a 3-line troubleshooting note: what 'connection refused', 'access denied' and error 1046 each mean and the fix. Target: Note saved in your .sql file, no passwords inside

    /* refused: server stopped or wrong host/port */ /* access denied: wrong user/password */ /* 1046: run USE portfolio_retail_lab; */

Up next · Lesson 3

Import and explore the shop data

80 min · 19 practice problems

Start next lesson
What a database is Import and explore the shop data