Inequalities with aws_sdb

I'm using aws_sdb_proxy for accessing SBD. Since it is using ActiveResource (REST approach), querying with equalities is fairly simple. All the equalities can be passed as a hash with the :params parameter.

Balloon.find(:all, :params => {:color=> "green", :size => "5inch"})

which will be resolves to below GET request:

http://localhost:8080/Baloons.xml?color=green&size=small

In order to support all the other sql-like queries, sdb_proxy allows users to pass a hard-coded string value. Because ActiveResource is used as the underlying communication mechanism, :params value has to be a hash event though all we need to pass is a string. aws_proxy goes around this problem with only looking at the first key of the hash in the case of hard-coded query string.

Balloon.find(:all, :params => {" ['size' > '5inch'] sort 'size' " => nil})

and this will resolve to below GET request:

http://localhost:8080/Baloons/query.xml?:static_query

Note1: I added the query as static_query because I don't have my setup on this machine, but it will add corresponding UTF values for space, quotes and for brackets.. At the end will be something like http://localhost:8080/Baloons/query.xml?size**5inch**sort****size**
Note2: sdb_proxy is using site_prefix for the resource, so the object name (Baloon in this case) is not the domain name. This is a whole different point to discuss, I wrote this entry according to my altered version of sdb. If you are using sdb_proxy as it is, then your http requests will be similar to following:
http://localhost:8080/:domain_name/baloons/query.xml?:static_query
http://localhost:8080/:domain_name/baloons.xml?color=green&size=small

Links for SDB & Rails

Rails helper

Rails MVC

SDB

SDB-proxy

Synergy -sharing keyboard & mouse

Here are the instructions I followed.
Two things I had problems with:
- Reverse DNS (make sure your hostname and IP address resolves to each other correctly)
Here is how to check if your DNS resolves backward and forward correctly
>> dig +short hostname
>> dig +short -x your_ip_address
- Make sure the hostname you put in the server configuration matches the "Screen name" in your client.

Then you are good to go! :-)