Slow display of PostGIS tables

Question

I am using QGIS 1.8 + PostGIS 2.x.

I have the problem that my PostgreSQL tables are displayed very slow when I scroll them in QGIS. I have no problem with other tested GIS (e.g. UDig, GVSig, ArcGIS Dedktop). The number of objects isn't large (5000-10000) and the rendering is no problem.

I've observed that every action like scrolling causes queries in the database, looks like there's no cache.

The connection to the database server runs through a fast Internet (and it works with other GIS).

Does anyone have an idea how to solve the problem?

I would love to work with QGIS, but the problem makes it impossible so far.

Answer 1

I have a local postgis database with about 10K polygons and found that usability (less flickering and faster dispaly) improves a lot when I set the following options in qgis under the rendering tab.

setting the first option to zero instructs qgis to avoid partial refreshes which IMHO cause a lot of flickering. The second option enables render caching.

I have not found any option with regards to postgis query caching so it might be that qgis hits the database on every scroll/pan.