mirror of https://github.com/apache/lucene.git
75 lines
1.9 KiB
Plaintext
75 lines
1.9 KiB
Plaintext
Description of Surround:
|
|
|
|
Surround consists of operators (uppercase/lowercase):
|
|
|
|
AND/OR/NOT/nW/nN/() as infix and
|
|
AND/OR/nW/nN as prefix.
|
|
|
|
Distance operators W and N have default n=1, max 99.
|
|
Implemented as SpanQuery with slop = (n - 1).
|
|
An example prefix form is:
|
|
|
|
20n(aa*, bb*, cc*)
|
|
|
|
The name Surround was chosen because of this prefix form
|
|
and because it uses the newly introduced span queries
|
|
to implement the proximity operators.
|
|
The names of the operators and the prefix and suffix
|
|
forms have been borrowed from various other query
|
|
languages described on the internet.
|
|
|
|
|
|
Query terms from the Lucene standard query parser:
|
|
|
|
field:termtext
|
|
^ boost
|
|
* internal and suffix truncation
|
|
? one character
|
|
|
|
|
|
Some examples:
|
|
|
|
aa
|
|
aa and bb
|
|
aa and bb or cc same effect as: (aa and bb) or cc
|
|
aa NOT bb NOT cc same effect as: (aa NOT bb) NOT cc
|
|
|
|
and(aa,bb,cc) aa and bb and cc
|
|
99w(aa,bb,cc) ordered span query with slop 98
|
|
99n(aa,bb,cc) unordered span query with slop 98
|
|
|
|
20n(aa*,bb*)
|
|
3w(a?a or bb?, cc*)
|
|
|
|
title: text: aa
|
|
title : text : aa or bb
|
|
title:text: aa not bb
|
|
title:aa not text:bb
|
|
|
|
cc 3w dd infix: dual.
|
|
|
|
cc N dd N ee same effect as: (cc N dd) N ee
|
|
|
|
text: aa 3d bb
|
|
|
|
For examples on using the Surround language, see the
|
|
test packages.
|
|
|
|
|
|
Development status
|
|
|
|
Not tested: multiple fields, internally mapped to OR queries,
|
|
not compared to Lucene's MultipleFieldQuery.
|
|
|
|
* suffix truncation is implemented very similar to Lucene's PrefixQuery.
|
|
|
|
Wildcards (? and internal *) are implemented with regular expressions
|
|
to allow further variations. A reimplementation using
|
|
WildCardTermEnum (correct name?) should be no problem.
|
|
|
|
Warnings about missing terms are sent to System.out, this might
|
|
be replaced by another stream, and tested for in the tests.
|
|
|
|
BooleanQueryTst.TestCollector uses a results checking method that should
|
|
be replaced by the checking method from Lucene's TestBasics.java.
|