QGIS: update query in db-manager fails

Question

I've created a layer with photos using the tools in QGIS. This yields a table, where each line contains a filepath to a photo. So far so good. But the paths are all absolute. I'd like to share this project with others and would like to make the paths relative.

I tried so using the DB manager, running this query:

update 
 "Fotos Mai 2022"
set
 photo = replace(photo, 'C:\Users\Username\Documents\GIS-Project', '..');

But as a response I get the error-message:

Query execution error on CREATE TEMP VIEW _tview AS update "Fotos Mai 2022" set photo = replace(photo, 'C:\Users\Username\Documents\GIS-Project', '..'): 1 - near "update": syntax error

How can I troubleshoot this issue?

Answer 1

Ok, new day, fresh brain, solution is easy: the error message reveals that I had attempted to change the database from the wrong angle: I had been trying to change table content while being connected to a virtual layer (in QGIS' DB Manager), not to an actual database.

To connect to the actual database, in DB Manager, go to the left-hand pane "Providers" and choose a database connection (or open an new one by right-click / new connection)