[req.find] Use vreg.schema.eschema for eschema lookup
If an etype is non-existant, using vreg.schema[etype] raises a confusing error
complaining about a non-existing relation. This is because of the
implementation of vreg.schema.__getitem__ that look first in entities and then
in relations.
Using directly vreg.schema.eschema restrict the lookup to etypes only, hence
raises a meaningful error when the etype does not exist.
.. winclude:: search_sample_queries
You can as well type complex queries using the RQL_ query language,
used every where to build dynamic pages of this site.
You can use one of the following prefixes to specify which kind of search you
want:
* `rql` : RQL query
* `text` : full text search
.. _RQL: doc/tut_rql