Deleting QGIS project stored in PostgreSQL using PyQGIS

Question

I would like to delete a .qgs project stored in PostgreSQL using PyQGIS. This SQL code does the job into pgAdmin :

DELETE FROM test2.qgis_projects WHERE name = 'Project_name';

My attempt which doesn't work in PyQGIS is :

from PyQt5.QtSql import *
uri = QgsDataSourceUri()
uri.setConnection("localhost", "5432", "BDtest", "postgres", "password")

db = QSqlDatabase.addDatabase("BDtest");
db.setHostName(uri.host())
db.setDatabaseName(uri.database())
db.setPort(int(uri.port()))
db.setUserName(uri.username())
db.setPassword(uri.password())
db.open()
query = db.exec_("""DELETE FROM test2.qgis_projects WHERE name = 'Project_name';""")
query.next()
query.value(0)
print(query)

This last code doesn't work in PyQGIS, could someone correct it?

I think it misses uri.setDataSource() but I do not know how to use it, because the data I need to delete is a qgis_project (there is no geometry).

Answer 1

The recommended way of removing a QGIS project stored in a database is this:

1. Build a proper uri

   For PostgreSQL, something like:

   'postgresql://user:password@localhost:5432?sslmode=disable&dbname=my_db&schema=my_schema&project=my_pg_project'
   

   Note the project=my_pg_project at the end of the uri.

2. Get the corresponding project storage object

   storage = QgsApplication.projectStorageRegistry().projectStorageFromUri(uri)
   

3. Remove the project

    storage.removeProject(uri)
   

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Related:

• How to load a QGIS project from a database.
• How to save a QGIS project to a database.