UK Postcode data

[Muttley08]

There's another vector product to be released in May as well - working @ OS at the moment if there's any questions I can help with...

[Durbs]

if there's any questions I can help with...

Can you ask them if i can have the Northern Irish and Manx Code-Point data?

[Muttley08]

Can you ask them if i can have the Northern Irish and Manx Code-Point data?

OSNI (OS Northern Ireland) are a seperate organisation - so no idea I'm afraid - never worked with NI data myself either! Not much help I know!

[Durbs]

OSNI (OS Northern Ireland) are a seperate organisation - so no idea I'm afraid - never worked with NI data myself either! Not much help I know!

Seems the Northern ireland info is included in the OS Code-Point paid version so i guess they license it from their Irish counterparts.

Unfortunately my Plan B really requires the NI and Isle of Man data so going to have to buy it somewhere, prices i've seen so far for postcode stuff from Royal Mail & OS are just though.

[fullyautomatix]

I have now imported the Code point post code data into SQL Server 2000. I havent yet migrated into 2008 ( in a few months I will). So anyway I cannot use the mumbo jumbo like spatial index and the like.

So there are about 1.5 million records in the table.

I have written a stored proc to fetch all the post codes within a certain defined distance of a particular post code.

When i try to find all post codes within 5 miles of, say , Se1 0AA I get back proper records but the query itself takes at least 5 seconds if not more.

Has anybody managed to get the queries run faster ? Is there a better algorithm ? I copied my algorithm from a MS article.

[Spacecadet]

Are you going to need to run this on the fly? I've had to do similar things before, but the centroid was already known.

The difficulty of working it out on the fly is that you're not going to be using indexes. If you are limiting the search radius then you can cut out most of the UK from your search. It's pointless including newcastle addresses when calculating the distance when your searching for a 5 mile radius from somewhere in Bath.

Work to a square first, this will allow you to go 5 miles east, west, north and south without having to do any fancy calculations. (you can index your lat/long northings/easting columns to help speed this bit up)
From that much smaller subset you can then workout what is in the 5 mile radius