[Qgis-user] Historical data in QGIS-PostGIS

[Richard Duivenvoorde]

On 11/14/20 12:11 AM, Vanildo Heleno Pereira wrote:
> Hello everyone.
> I would like to know if there is a possibility to work with historical versions of geographic data in QGIS / PostGIS?
> The geometries need to be stored in a single database table (PostgreSQL) and you will receive data (new records from the same location) annually and I need to visualize each one in a different layer.

Hi Vanildo,

What do you mean with 'historical version of geographical data'?
Is it that you have different versions of a certain geometric feature (be it a border, a street or an animal), and that versions actually has (should have) 2 (date)time columns, being 'first appearance' and 'last appearance'?
If so, this kind of data is to be viewed in a sort of 'time-frames'?

So say you have a set of streetdata, you could show a layer as: show me streets all streets of 1800-1900 as a dataset in which you have a filter like (first_appeareance > 1800 AND < 1900) or (last_appearance > 1800 AND < 1900) (or variations like this).
Then you can create views in the database with these filter queries, but you can also do that in different layers in QGIS (both if you want to be able to show different timeframes at a time)

You could also do this using the 'temporal controller' which is now in QGIS, then you kan keep it one layer and use the controller to show one certain 'time frame' at a time.

Or do I misunderstand you question?

Regards,

Richard Duivenvoorde