Calculate and filter on distance

robleer

Hi,

I want to run a query which calculates the distance between two zip codes. That's no problem because I can buy a zipcode table with positions, but after the calculation is made I want to add a filter so the user can limit the distance.

For instance, the user can say: give me all adresses within 50 km from here.

Is that possible and done somehow?

nlarson

Is the distance dynamic [per user] or static?

tford

If you provide some additional details it would be easier to help with the solution. Right now it's pretty general.

robleer

The distance is dynamic. I cannot store the distance from point a to b in the database.

Depending on the users location I need to calculated the distance to another point. I know how to do that, but I cannot find anything like a calculated field in an Aware query.

RLJB

Couldn't you just create a new field in the BO called Distance and put a rule in the BO with the calculation? Eg BO.Distance=BO.StartPoint-BO.EndPoint etc...(with your proper calc)

tford

Depending on the users location I need to calculated the distance to another point.

How are you collecting / storing the From and To points?

robleer

Tford,

I know the coordinates from a zipcode table here in the Netherlands.

The user who has logged in has a zip code. Then he starts a query to find some sportclubs (like soccesclubs, hockeyclubs a.s.o.). Those sportclubs have zipcodes to. Every sportclub can do this.

That means (in theory) that 7000 sportclubs in the Netherlands can run the query. If I have to store the distance in a table, that means 7000x7000 (49.000.000) records in the table. Of course this will be a little less, but I still do think that working this way is not correct because it can be done lot easier (in other webapps, just calculate it runtime).

So, i want to calculate the distance with a calculated query field.

nlarson

RLJB wrote
Couldn't you just create a new field in the BO called Distance and put a rule in the BO with the calculation? Eg BO.Distance=BO.StartPoint-BO.EndPoint etc...(with your proper calc)

This is what I was thinking, but into a non-persitent BO with fields like: UserID, UserStartLoc, DestinationLoc, Distance, etc. That way you can use it for each user without worring about record locking or odd search results from two folks using it at once.

tford

but into a non-persitent BO with fields like: UserID, UserStartLoc, DestinationLoc, Distance, etc. That way you can use it for each user without worring about record locking or odd search results from two folks using it at once.

That's the only solution I can think of also.

Some possible steps:
1) Using ZIP stored in LoggedInRegularUserBO

2) Run a process to create the non-persistent BO instances nlarson mentioned above

3) Run query on BO from #2

robleer

Mmmm, maybe this works....

I'm off for a short holiday and try it next week.

Thanks for you help so far !