Not all versions need to upgrade the database.
You can see a list of database versions for each release at https://codex.ww.wp.xz.cn/WordPress_Versions and you can find your database’s version in your _options table at db_version.
Hi,
I know that all release don’t need to upgrade database.
But it’s not asking for database upgrade between 3.9 and the latest version (4.2.2) whereas other wordpress I maintain asked for it.
I check the value of db_version. It seems correct, it have the same number of a fresh wordpress intallation.
If the db_version is correct, then the database was updated, you just didn’t notice. 🙂
I think I’ve encountered the same thing as the OP. When I upgrade a number of sites all from the same version, say 4.2.1 to 4.2.2, some will prompt me to click a button for a database upgrade, and others do it without requiring that I click the button.
If the db_version is correct, then it happened in the background automatically, or someone else pushed the button. 🙂
I know nobody else clicked the button. : )
So what determines whether or not it happens in the background or a button must be clicked? That may answer the question.
The type of updater generally. If it’s a core update, you’ll need to click manually (note that everyone sees this, even visitors, so yes sometimes someone else might click it for you). You can also modify it with a plugin so that’s done automatically, and many hosting provider one-click installers do the full update automatically.
