karussell

Why is there no such DataImportHandler thing in ElasticSearch? Uhm, well ... but because:

1. You should really consider your own scripts 
(be it jvm based, perl, ruby, php, nodejs/javascript) 
to feed ElasticSearch via bulk indexing: 
http://www.elasticsearch.org/guide/reference/java-api/bulk.html

2. There are two projects doing it already:
 * http://code.google.com/p/sql-to-nosql-importer/
 * https://github.com/Aconex/scrutineer (keeps DB in synch with ES or solr!)

karussell

Several times in a month there pop up questions regarding query structure on the ElasticSearch user group.

Although there are good docs explaining this in depth probably the bird view of the Query DSL is necessary to
understand what is written there. There is even already some good external documentation available:
http://www.elasticsearch.org/tutorials/2011/08/28/query-dsl-explained.html

And there were attempts to define a schema:

http://groups.google.com/group/json-schema/browse_thread/thread/ae498ee818155d50
https://gist.github.com/8887766ca0e7052814b0