[ZDP] BackTalk to Document The Zope Book (2.5 Edition)/Searching and Categorizing Content
Thu, 12 Sep 2002 06:55:28 -0400
A comment to the paragraph below was recently added via http://www.zope.org/Documentation/Books/ZopeBook/current/SearchingZCatalog.stx#3-100
Here are some examples queries and their results to show how the
'level' attribute works:
% jshell - Aug. 8, 2002 5:54 pm:
This example full of aa's and bb's and such is very hard to follow, especially when wanting the answer "do
path indexes do Depth based searching?"
For example, WebDAV (and also Exchange 2000, LDAP, etc) have the concept of Depth in their queries. A query
of 'depth 0' means 'search/match ONLY the object specified (no children)'. A query of 'depth 1' means
'search/match the object specified and its immediate children, but no further'. This yields results similar
to calling 'objectValues()' in an ObjectManager. 'depth infinite' means 'search/match from this particular
point in the tree, downward to infinity'.
It seems every other tree based storage system has the concept of 'depth' in their query languages, and Path
Indexes still seem broken without it.
% Anonymous User - Sep. 12, 2002 6:55 am:
This 'level' concept needs more explaining. I guess that level=0 means
that the path is interpreted as absolute starting from the root, -1 means
relative/starting from anywhere in the path and the other values means
absolute starting as the nth path element in the searched path.
I second the opinion that the example with all the 'bb's is difficult to