handling of Change-Only Updates?

[metazool]

One reason to use the proprietary alternatives to this package is their handling of the Change-Only Updates that OS distribute as GML.

Does the Astun Loader handle the COUs and/or are there plans to?

[walkermatt]

Hi @metazool, long time no speak! There is no support for OSMM Topo CoU at the moment. @aileenheal has been experimenting recently to streamline the update of our mapping services, we might have some news on progress in the next few weeks.

[metazool]

Any latest updates on this? :)

[walkermatt]

Hi @metazool good to hear from you. We do have something working in-house based on Postgres but we're not currently in a position to release it at the moment.

[xaadim]

Any latest updates on this? :)

[melmorg1]

Any update on this please?

[zymurgic]

I've done an interim workaround for this, which is to write a different script to run after the COU data load.
OS include 'osgb:DepartedFeature' elements in the COU data sets.
My script looks for osgb:DepartedFeature in every file of the the source data, and use the fid to delete from the topographicarea, topographicline, cartographictext, cartographicsymbol and topographicpoint tables in the PostgreSQL database.
Would be better to have it as part of the loader script (my script is in PHP because I'm more familiar with that than python and it was a quick hack).

OS also include 'fvds' feature validation dataset, though it's quite an intensive process to load that whole lot, and then delete the features in your database that aren't in that list.

[zymurgic]

Work also to be done after loading a COU update will include removing superseded features that have a newer version in the database for the same fid.
You will require an additional index in the database tables for the boundaryline, cartographicsymbol, cartographictext, topographicarea, topographicline, topographicpoint on the fid column, or it will take forever.