Database Size And Largest Tables

How the database size check works

During each snapshot your site adds up the data and index size of every one of its own tables, the ones with its table prefix. That total is what the Snapshot tab shows, with an arrow when it has changed since the last snapshot. The arrow is never red, because this check is for information only and never raises a warning.

Investigate lists the ten largest tables, each with its size, estimated rows and share of the total. It also shows the size of the whole database, including anything that belongs to other installs, and how much of that is mySites.guru’s own scan tables.

All sizes are the database server’s estimate. On InnoDB they are approximate. If your site cannot read the sizes, the row shows No Data rather than 0 B.

What usually makes a table large

Next to each of the ten largest tables, Investigate names the usual reason when it recognises the table:

• Sessions. Joomla clears these on its own schedule.
• The Joomla Smart Search index, which shrinks when you rebuild it.
• Content version history.
• The 404 log kept by Joomla’s Redirect plugin.
• The Joomla user action log, which has its own Action Log Size check.
• WordPress options, where autoloaded options are worth checking, and post meta.
• Action Scheduler logs and WooCommerce sessions.
• Comments, which are often spam.

Using the figures

No fix is needed. Use the figures to spot the table that is growing:

1. Open the site in mySites.guru, go to the Snapshot tab and click Investigate on the Database Size And Largest Tables row.
2. Look at the top of the list. A log, history or session table near the top is usually the one to deal with.
3. Clear it the way its own extension or plugin intends, rather than emptying it in the database by hand.
4. Watch the next snapshots to see whether the size comes back down and stays there.

A database that is much larger than its own tables often means an old install or a staging copy is sharing it. The tables from another install check finds those.