Memory Table Provider

Topics: SharpMap v0.9 / v1.x, SharpMap v2.0
Developer
Oct 18, 2011 at 4:07 AM
Edited Oct 18, 2011 at 4:08 AM

 I'm planning to develop a more MemoryDatatableProvider and add some features such as insert, update, delete, ... on the memory table. Then add the save edit function to save from memory table to datasource necessary. Is there anything similar that?

Developer
Oct 20, 2011 at 4:11 AM

I found it in here: http://sharpmap.codeplex.com/workitem/7873. Sharpmap v2.x version have implemented.

Coordinator
Oct 20, 2011 at 6:11 AM

There is also GeometryFeatureProvider in SharpMap v0.9

Developer
Oct 20, 2011 at 7:13 AM

Thanks FObermaier,

I will add some function for update and delete rows to GeometryFeatureProvider for my need. I hope i will have tool edit is faster than the present :)

Maybe the same to ArcGIS :)

TrieuVy.

Developer
Oct 31, 2011 at 4:24 AM

I have completed some functions such as: insert, update, delete rows of GeometryFeatureProvider class. Use GeometryFeatureProvider is faster but it is not as fast as I had expected.

GetGeometriesInView function is slow when we have a lot of rows in FeatureDataTable. Maybe, we should add index or hash table for Geometries into FeatureDataTable for faster or how to it faster?

TrieuVy.

Coordinator
Oct 31, 2011 at 7:31 AM

TrieuVy, how many rows do you have?

You can certainly add a spatial index. The ShapeFile provider uses the quadtree implementation from SharpMap.Utilities.Indexing.

Currently it does not change if you alter geometries or remove geometries, but you can add new ones.

Hth FObermaier

Developer
Oct 31, 2011 at 9:40 AM

Hi FObermaier,

My test data is 10776 Polygons.

PostGIS provider: use spatital index for geometries

- Faster when zoom in ( a little geometries in bbox) : Edit fast ( realtime :ok)

- Slower when zoom out. When zoom to extent  take about  >1 minute ( this is a limitation in my application)

GeometryFeatureProvider

- I seem to meet almost not much different time in different zoom levels. Slower than postgis when zoom in ( a little geometries in bbox )  and faster than postgis when zoom to extent.

When zoom to extent take about 10 seconds


I will try to add Quadtree to GeometryFeatureProvider. I do not have much experience with it

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I do not have much experience with it