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Tag: mysql

MySQL binlog files are taking up all disk space

I am running Flywheel’s Local app on a MacBook Pro and noticed that I was constantly running out space on my MacBook’s SSD. Even after I cleared big chunks of space it would quickly fill up and run out of space.

The problem was MySQL and its binary log files (located at /Users/<username>/Library/ApplicationSupport/Local/run/<random-hash>/mysql/data) – the new binlog files kept on appearing and eventually would fill up all the available space on the SSD.

Add the following line to the [mysqld] section of the MySQL server configuration file template (my.conf.hbs). It is located in the /app/cnf/ directory of your Local’s site.

expire_logs_days = 3

The following will tell the MySQL server to only keep the binary log files for up to 3 days and delete the older ones.

Alternatively, you can add the following (which will completely disable the logging)


Restart the MySQL server and you will see that the old bin files will shortly disappear.

Note: do not delete the bin files manually – let the MySQL server handle it by using the expire_logs_days configuration.

Can’t edit database schema in WordPress running on Flywheel Local 5.x


I am using Flywheel’s Local (5.6.x) app for running WordPress development instances on my MacBook locally.

One day, I logged in to a WordPress installation, clicked on Add a New Post and was greeted with a somewhat more bare than usual edit screen:

  • All post’s custom meta boxes were missing.
  • Publish button was missing and replaced with Submit for review button.
  • When clicking on Submit for review button I was shown an error saying that I did not have enough permissions perform that action.


I de-activated all the plugins to rule out any interference of their code with WordPress core – the issues remained with all plugins de-activated.

I checked the current user and confirmed that it has correct administrator roles set up. I also logged in as another administrator account and observed the same issue with adding posts.

I restarted the web and MySQL servers – it didn’t help.

Then, I turned my attention to PHP error logs – I ran “tail -f error_log” command and tried adding a new post. The recorded in the log error showed that SQL query failed because a post with ID 0 already existed:

Duplicate entry '0' for key 'PRIMARY' for query INSERT INTO wp_posts...

I quickly checked if auto-increment was enabled for the ID field in wp_posts table and … it was not!


I found a problem – there was no auto-increment enabled for the ID field in the wp_posts table.

When, I started my MySQL database client and enabled auto-increment, I could not save the changes. MySQL server complained that the default value (0000-00-00 00:00:00) for post_date field was invalid.

Incorrect datetime value: '0000-00-00 00:00:00' for column 'post_date' at row ...

Errors like above in MySQL happen when “NO_ZERO_DATE” is set as one of the MySQL modes. Please read for more details.

To change the value of MySQL mode when running it in Flywheel’s Local app you need to edit a template for mysql.conf file called my.conf.hbs. It is located in /app/cnf/ directory of your site within Local app. Add the following to [mysqld] section. You need to make sure that there are no NO_ZERO_IN_DATE and NO_ZERO_DATE in the value of sql-mode variable.



Once saved, restart your site within Local app, edit the wp_posts table add auto-increment to ID field.

Once the changes are saved, you can remove the line you added to my.conf.hbs file and restart the server.