I have a large table in Postgis2. It has >500 million polygon, line and point features all happily living in there and the table performs brilliantly in other GIS.

I am now trying to just add that table to a project in QGIS but here is the thing, why does it take so long?

When i try to 'Add PostGIS overlay' it says detecting for about 4 hours to tell there are 3 geometry types. OK, i can take that if i only have to do it once...

Once it finishes that i select all three parts click ok.. so far im 2 days into trying to get it to load into the canvas.

What is going on? I am zoomed in so only a few polygons should be rendered on screen.

Is this an error or a 'feature' of QGIS? Is there something i need to specifically do to enhance the performance for QGIS?

Many thanks for your help people.

Update:

Thanks for the help.
I am using MapInfo and Cadcorp SIS both of which love the "everything in one place" model rather than the splitting it up, join it back later with queries model. And thanks @AndrewJoost, the estimated metadata saved about an hour but still it takes a few hours too long and misses one of the geometry types off the list... QGIS not supporting mixed geometries in one overlay is no problem, as long as it supports them in one table.
And the way it does this with a filter is great for small tables but just fails when you have a large one it seems.

I am unable to seperate the table into three parts as this does not make sense for the other systems using the data, and would also break them.

@NathanW How can i get 3 records for a single table into the geometry_columns view now that it is no longer a physical table? any ideas? Sorry about all the newbie questions

Any other ideas to stop QGIS trying to be helpful and scanning a table before allowing me to add it? I dont mind choosing geometry types by hand for every overlay if thats what it takes?

Cheers