Docs: Add clarifying text about regexp and terms

For the casual reader, the reference to "term queries" may be glossed over, yielding an unexpected result when using `regexp` queries.
This attempts to make that distinction more prominent.

Closes #6698
This commit is contained in:
Matthew L Daniel 2014-07-03 11:39:08 +02:00 committed by Clinton Gormley
parent 38e9942bd6
commit 53f2301eea
1 changed files with 4 additions and 1 deletions

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@ -3,6 +3,9 @@
The `regexp` query allows you to use regular expression term queries.
See <<regexp-syntax>> for details of the supported regular expression language.
The "term queries" in that first sentence means that Elasticsearch will apply
the regexp to the terms produced by the tokenizer for that field, and not
to the original text of the field.
*Note*: The performance of a `regexp` query heavily depends on the
regular expression chosen. Matching everything like `.*` is very slow as
@ -49,7 +52,7 @@ You can also use special flags
Possible flags are `ALL`, `ANYSTRING`, `AUTOMATON`, `COMPLEMENT`,
`EMPTY`, `INTERSECTION`, `INTERVAL`, or `NONE`. Please check the
http://lucene.apache.org/core/4_3_0/core/index.html?org%2Fapache%2Flucene%2Futil%2Fautomaton%2FRegExp.html[Lucene
http://lucene.apache.org/core/4_9_0/core/org/apache/lucene/util/automaton/RegExp.html[Lucene
documentation] for their meaning