On 1/9/07, Ryan McKinley <[EMAIL PROTECTED]> wrote:
I would like to use faceted browsing to group documents by year,
month, and day.
I don't know what your particular use-case is, but this might be a job
for facet hierarchies.
http://www.nabble.com/Hierarchical-Facets--tf2560327.html#a7135353
No, there isn't anything implemented in Solr yet... but then again,
built in faceting didn't even exist in Solr until 4 months ago :-)
I'm pretty sure we could handle the computational requirements, it's
more a matter of defining useful generic semantics and the interface.
Option 1:
Add three fields, one for year, month, day. Something like:
<field name="addedTime" type="date" indexed="true" stored="true" />
<field name="addedTimeYEAR" type="string" ... />
<field name="addedTimeMONTH" type="string" ... />
<field name="addedTimeDAY" type="string" ... />
then use copyField to generate the various versions:
<copyField source="addedTime" dest="addedTimeYEAR"/>
<copyField source="addedTime" dest="addedTimeMONTH"/>
<copyField source="addedTime" dest="addedTimeDAY"/>
this would somehow convert the original date format for each copy:
addedTime = "2007-01-08T21:36:15.635Z"
addedTimeYEAR = "2007"
addedTimeMONTH = "2007-01"
addedTimeDAY = "2007-01-08"
Perhaps this requires a custom FieldType for Y/M/D to convert the
larger string to the smaller one.
pros:
* Can use SimpleFacets directly
cons:
* seems messy. particularly since i have multiple fields i'd like to
have the same behavior.
There's also a question of if you would really want a breakdown by
each day (if you had 10 years of data say) returned to the client. It
starts to be a lot of data. That's what made me think of a hierarchy
where you could start out at a higher level and drill down. Of
course, that's possible with simple facets too I guess (via filtering)
Option 2:
Add an analyzer to the date field that adds multiple Tokens with
various resolutions, then write a custom faceter that knows a string
length 4=year, y=month, 10=day. Or, perhaps it could look at the
token name.
I don't think adding to the same field buys you much (anything?) over
adding to a different field. In any case, you could also do simple
faceting on this field as-is if your client has knowledge of the
different lengths of strings.
schema.xml:
<fieldtype name="fdate" class="solr.DateField">
<analyzer type="index" class="...DateFacetAnalyzer"/>
</fieldtype>
DateFacetAnalyzer:
Token t = new Token( date, 0, date.length(), "original" );
t.setPositionIncrement( 0 );
tokens.add( t );
t = new Token( date, 0, 4, "year" );
t.setPositionIncrement( 0 );
tokens.add( t );
t = new Token( date, 0, 7, "month" );
t.setPositionIncrement( 0 );
tokens.add( t );
...
pros:
* simple / reusable
cons:
* I don't fully understand how it would affect search & sorting
Any thoughts / pointers / advice?
thanks
ryan
-Yonik
