Thanks, Nick - that clears up the mystery.
Just for my own curiosity and edification (I’m a programmer, too) I’m wondering if you can confirm something for me. I imagine Local WP works something like this: When a WordPress site is started, the site gets database service via Local WP rather than a separate installation of MySQL. And to provide that service, Local WP reads the local.sql file and uses the contents to create and populate the database, tables, stored procedures etc. on the fly, either in temporary storage or in memory. When the WordPress site is stopped, the current state of the database is saved to the local.sql file. Is that a reasonably accurate description of how it all works?
My assumption that the database is created in temporary storage or in memory is based on the fact that as I’m changing the site’s contents in real time (by modifying or adding blog posts, for instance), the Last Modified time-stamp on the local.sql file remains unchanged. Based on that time-stamp, it seems that the file is only updated when the site is shut down. So the database changes that have accumulated while the site is up must have been saved either in memory or to some temporary storage location.
I’m curious about all this because I’ve spent many years building database applications (mostly MS SQL Server) and for those applications the database itself is always a separate file (or files) from any script file that may manipulate the database.
Thanks again for your help with this.