The British Caving Association

Footleg wrote:Hi Cookie,

This is not really the right forum topic for this, so please let me know where the best place is to discuss the National Cave Registry. I am very interested in this project (and having been learning a bit of PHP and MySQL in order to deal with GPS data on the ULSA website I might be able to help out?). I've also been collecting data via GPS for Yorkshire caves, which I cannot find a public source of.

Footleg

Hi Footleg,

Here is a good place for it.

I appreciate your offer and would like to take you up on it. I have it all spec'd out in my head and some of it even written down, but can't find the time to do the actual coding.

Have a look at the proposal on http://www.british-caving.org.uk/?page=30. Things have moved on since I wrote it, but its broadly correct.

Some of the key points:

* The National Registry acts as a index into the distributed local registries.

* The National Registry's contribution is the allocation of the unique reference number.

* The work is distributed because one person alone can not do this.

* Start simple and expand it later.

* The data contributers retain control over their data.

There is plenty of other stuff as well, the coding is almost the easy bit.

Lets talk at Hidden Earth.

Have a look at the proposal on http://www.british-caving.org.uk/?page=30. Things have moved on since I wrote it, but its broadly correct.

Looks like a comprehensive and sensible proposal. A couple of suggestions though.

1) Limiting SIDs to four digits assumes that there will be less than 10000 sites per county. I would suggest it safer to use five digits for future proofing the system.

2) RE: The suggestion to limit location information to 1km resolution: I think this is the wrong approach. Internally the database has to store location information to at least 10m resolution in order to record where a site is. However this field should have restricted access and a second field be used to store the published location. This second field can be expressed to an appropriate resolution for the site. Publicly known caves can be given to 10m (OS grid ref. format like AA 0000 0000). Sensitive locations can be expressed to 1km resolution.

I suggest 10m resolution as this tends to eliminate variations in typical GPS readings for the same site, and helps to distinguish between duplicate entries and closely located sites.