I was quite nosing around looking for something else, and came across this:

> Until MariaDB 10.2.3, InnoDB and XtraDB used an auto-increment counter that is stored in memory. When the server restarts, the counter is re-initialized to the highest value used in the table, which cancels the effects of any AUTO_INCREMENT = N option in the table statements.

Of course. We knew that. What we didn't know, possibly, was the following:

>  From MariaDB 10.2.4, this restriction has been lifted and AUTO_INCREMENT is persistent.

Note that this isn't the current package version of mariadb-server for Debian 9, it's lagging behind a bit at 10.1.26. However, the days of auto increment issues, at least for MariaDB, may soon be coming to a close.

Information from: https://mariadb.com/kb/en/library/auto_increment/

Liz Rea
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