Implement diffs that only store changes. For example if a node position doesn't change we don't store the lat/lon again. The same for its tags or a relation's members or a node's ways.

• Node:
  • Tags
  • Lat/Lon
• Way:
  • Nodes
  • Tags.
• Relation:
  • Members
  • Tags.

Reasoning:

In a lot of cases only tags will change or only positions. When splitting a way only the nodes set changes. This will reduce diskspace used for a diff even further.

The read-me mentions a nuget package and suggests running Install-Package OsmSharp.Db.Tiled which fails. Nuget.org doesn't show anything for "OsmSharp.Db.Tiled" and there are no packages listed here on the github project.

Where can I find the nuget package?

Now we convert from and to (x,y) <-> (localid) all the time, we should use uint ids internally and only convert them when they become public.

Implement compressed tiling. Tiles are too big for now.

Not all tiles change, add a method returning in what db the latest version of a tile is located relative to the current database.

Diff encode tile ids in tiled streams, there can be a lot and they are usually close together.

Postprocess the tile stream to reduce its size:

• Diff encode pointers with a 1 off to indicate last elements.
• Use VarUInt64 to store pointers.
• Store pointers after the actual objects: When we move to a next object we are always reading the objects but sometimes we need to read objects without needing pointers.

Implement indexer based just on tiles alone.

https://github.com/xoofx/zio/blob/master/readme.md