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I have previously used ArcSDE technology with Microsoft SQL Server to allow for multi-user database editing.
My ESRI licenses have recently ran out and I have been using QGIS for my GIS work. I am now thinking of using QGIS to create a database on Postgres/PostGIS so I can give multiple people in my department the capability to edit and create GIS data on the same database. I am hoping to use only free and open source software for this and was wondering if I would need a server as well to fulfil these requirements?