ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'

Question

You'll need to start MySQL before you can use the mysql command on your terminal. To do this, run brew services start mysql. By default, brew installs the MySQL database without a root password. To secure it run: mysql_secure_installation.

To connect run: mysql -uroot. root is the username name here.

It's probably because MySQL is installed but not yet running.

To verify that it's running, open up Activity Monitor and under "All Processes", search and verify you see the process "mysqld".

You can start it by installing "MySQL.prefPane".

Here is the complete tutorial which helped me: http://obscuredclarity.blogspot.in/2009/08/install-mysql-on-mac-os-x.html

This happened after the homebrew install and occurs due to permission issues. The following commands fixed the issue.

sudo chown -R _mysql:mysql /usr/local/var/mysql

sudo mysql.server start

Run: brew info mysql

And follow the instructions. From the description in the formula:

Set up databases to run AS YOUR USER ACCOUNT with:
    unset TMPDIR
    mysql_install_db --verbose --user=`whoami` --basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmp

To set up base tables in another folder, or use a different user to run
mysqld, view the help for mysql_install_db:
    mysql_install_db --help

and view the MySQL documentation:
  * http://dev.mysql.com/doc/refman/5.5/en/mysql-install-db.html
  * http://dev.mysql.com/doc/refman/5.5/en/default-privileges.html

Hope this helps.

As others have pointed out this is because MySQL is installed but the service isn't running. There are many ways to start the MySQL service and what worked for me is the below.

To start the service:

1. Go to "System Preference"
2. At the bottom pane there should be MySql icon.
3. Double click that to launch the 'MySQL Server Status' and press the button 'Start MySQL Server'

My env:

Mac Yosemite 10.10.3

Installed Package: /Volumes/mysql-advanced-5.6.24-osx10.8-x86_64