cursor |
Retrieves a cursor value you can use to page through large result
sets. Use the size parameter to control the number of hits
to include in each response. You can specify either the
cursor or start parameter in a request; they
are mutually exclusive. To get the first cursor, set the cursor value to
initial. In subsequent requests, specify the cursor value
returned in the hits section of the response.
For more information, see Paginating
Results in the Amazon CloudSearch Developer Guide. |
expr |
Defines one or more numeric expressions that can be used to sort
results or specify search or filter criteria. You can also specify
expressions as return fields.
You specify the expressions in JSON using the form
{"EXPRESSIONNAME":"EXPRESSION"}. You can define and use
multiple expressions in a search request. For example:
{"expression1":"_score*rating", "expression2":"(1/rank)*year"}
For information about the variables, operators, and functions you can
use in expressions, see Writing
Expressions in the Amazon CloudSearch Developer
Guide. |
facet |
Specifies one or more fields for which to get facet information,
and options that control how the facet information is returned. Each
specified field must be facet-enabled in the domain configuration. The
fields and options are specified in JSON using the form {\"FIELD\":{\"OPTION\":VALUE,\"OPTION:\"STRING\"},\"FIELD\":{\"OPTION\":VALUE,\"OPTION\":\"STRING\"}}.
You can specify the following faceting options:
buckets specifies an array of the facet values or
ranges to count. Ranges are specified using the same syntax that you use
to search for a range of values. For more information, see Searching
for a Range of Values in the Amazon CloudSearch Developer
Guide. Buckets are returned in the order they are specified in the
request. The sort and size options are not
valid if you specify buckets.
size specifies the maximum number of facets to
include in the results. By default, Amazon CloudSearch returns counts
for the top 10. The size parameter is only valid when you
specify the sort option; it cannot be used in conjunction
with buckets.
sort specifies how you want to sort the facets in
the results: bucket or count. Specify
bucket to sort alphabetically or numerically by facet value
(in ascending order). Specify count to sort by the facet
counts computed for each facet value (in descending order). To retrieve
facet counts for particular values or ranges of values, use the
buckets option instead of sort.
If no facet options are specified, facet counts are computed for all
field values, the facets are sorted by facet count, and the top 10
facets are returned in the results.
To count particular buckets of values, use the buckets
option. For example, the following request uses the buckets
option to calculate and return facet counts by decade.
\{"year":\{"buckets":["[1970,1979]","[1980,1989]","[1990,1999]","[2000,2009]","[2010,\}"]\}\}
To sort facets by facet count, use the count option. For
example, the following request sets the sort option to
count to sort the facet values by facet count, with the
facet values that have the most matching documents listed first. Setting
the size option to 3 returns only the top three facet
values.
{"year":{"sort":"count","size":3}}
To sort the facets by value, use the bucket option. For
example, the following request sets the sort option to
bucket to sort the facet values numerically by year, with
earliest year listed first.
{"year":{"sort":"bucket"}}
For more information, see Getting
and Using Facet Information in the Amazon CloudSearch Developer
Guide. |
filterQuery |
Specifies a structured query that filters the results of a search
without affecting how the results are scored and sorted. You use
filterQuery in conjunction with the query
parameter to filter the documents that match the constraints specified
in the query parameter. Specifying a filter controls only
which matching documents are included in the results, it has no effect
on how they are scored and sorted. The filterQuery
parameter supports the full structured query syntax.
For more information about using filters, see Filtering
Matching Documents in the Amazon CloudSearch Developer
Guide. |
highlight |
Retrieves highlights for matches in the specified
text or text-array fields. Each specified
field must be highlight enabled in the domain configuration. The fields
and options are specified in JSON using the form {\"FIELD\":{\"OPTION\":VALUE,\"OPTION:\"STRING\"},\"FIELD\":{\"OPTION\":VALUE,\"OPTION\":\"STRING\"}}.
You can specify the following highlight options:
format: specifies the format of the data in the text
field: text or html. When data is returned as
HTML, all non-alphanumeric characters are encoded. The default is
html.
max_phrases: specifies the maximum number of
occurrences of the search term(s) you want to highlight. By default, the
first occurrence is highlighted.
pre_tag: specifies the string to prepend to an
occurrence of a search term. The default for HTML highlights is <em>. The default for
text highlights is *.
post_tag: specifies the string to append to an
occurrence of a search term. The default for HTML highlights is </em>. The default for
text highlights is *.
If no highlight options are specified for a field, the returned field
text is treated as HTML and the first match is highlighted with emphasis
tags: <em>search-term</em>.
For example, the following request retrieves highlights for the
actors and title fields.
{ "actors": {}, "title": {"format": "text","max_phrases": 2,"pre_tag": "","post_tag": ""} }
|
partial |
Enables partial results to be returned if one or more index
partitions are unavailable. When your search index is partitioned across
multiple search instances, by default Amazon CloudSearch only returns
results if every partition can be queried. This means that the failure
of a single search instance can result in 5xx (internal server) errors.
When you enable partial results, Amazon CloudSearch returns whatever
results are available and includes the percentage of documents searched
in the search results (percent-searched). This enables you to more
gracefully degrade your users' search experience. For example, rather
than displaying no results, you could display the partial results and a
message indicating that the results might be incomplete due to a
temporary system outage. |
query |
[required] Specifies the search criteria for the request. How you
specify the search criteria depends on the query parser used for the
request and the parser options specified in the
queryOptions parameter. By default, the simple
query parser is used to process requests. To use the
structured, lucene, or dismax
query parser, you must also specify the queryParser
parameter.
For more information about specifying search criteria, see Searching
Your Data in the Amazon CloudSearch Developer
Guide. |
queryOptions |
Configures options for the query parser specified in the
queryParser parameter. You specify the options in JSON
using the following form {\"OPTION1\":\"VALUE1\",\"OPTION2\":VALUE2\"...\"OPTIONN\":\"VALUEN\"}.
The options you can configure vary according to which parser you
use:
defaultOperator: The default operator used to
combine individual terms in the search string. For example:
defaultOperator: 'or'. For the dismax parser,
you specify a percentage that represents the percentage of terms in the
search string (rounded down) that must match, rather than a default
operator. A value of 0% is the
equivalent to OR, and a value of 100% is equivalent to AND. The
percentage must be specified as a value in the range 0-100 followed by
the percent (%) symbol. For example, defaultOperator: 50%. Valid values:
and, or, a percentage in the range 0%-100%
(dismax). Default: and (simple,
structured, lucene) or 100
(dismax). Valid for: simple,
structured, lucene, and
dismax.
fields: An array of the fields to search when no
fields are specified in a search. If no fields are specified in a search
and this option is not specified, all text and text-array fields are
searched. You can specify a weight for each field to control the
relative importance of each field when Amazon CloudSearch calculates
relevance scores. To specify a field weight, append a caret
(^) symbol and the weight to the field name. For example,
to boost the importance of the title field over the
description field you could specify: "fields":["title^5","description"].
Valid values: The name of any configured field and an optional numeric
value greater than zero. Default: All text and
text-array fields. Valid for: simple,
structured, lucene, and
dismax.
operators: An array of the operators or special
characters you want to disable for the simple query parser. If you
disable the and, or, or not
operators, the corresponding operators (+, |,
-) have no special meaning and are dropped from the search
string. Similarly, disabling prefix disables the wildcard
operator (*) and disabling phrase disables the
ability to search for phrases by enclosing phrases in double quotes.
Disabling precedence disables the ability to control order of precedence
using parentheses. Disabling near disables the ability to
use the ~ operator to perform a sloppy phrase search. Disabling the
fuzzy operator disables the ability to use the ~ operator
to perform a fuzzy search. escape disables the ability to
use a backslash (\) to escape
special characters within the search string. Disabling whitespace is an
advanced option that prevents the parser from tokenizing on whitespace,
which can be useful for Vietnamese. (It prevents Vietnamese words from
being split incorrectly.) For example, you could disable all operators
other than the phrase operator to support just simple term and phrase
queries: "operators":["and","not","or", "prefix"].
Valid values: and, escape, fuzzy,
near, not, or,
phrase, precedence, prefix,
whitespace. Default: All operators and special characters
are enabled. Valid for: simple.
phraseFields: An array of the text or
text-array fields you want to use for phrase searches. When
the terms in the search string appear in close proximity within a field,
the field scores higher. You can specify a weight for each field to
boost that score. The phraseSlop option controls how much
the matches can deviate from the search string and still be boosted. To
specify a field weight, append a caret (^) symbol and the
weight to the field name. For example, to boost phrase matches in the
title field over the abstract field, you could
specify: "phraseFields":["title^3", "plot"]
Valid values: The name of any text or
text-array field and an optional numeric value greater than
zero. Default: No fields. If you don't specify any fields with
phraseFields, proximity scoring is disabled even if
phraseSlop is specified. Valid for:
dismax.
phraseSlop: An integer value that specifies how much
matches can deviate from the search phrase and still be boosted
according to the weights specified in the phraseFields
option; for example, phraseSlop: 2. You must also specify
phraseFields to enable proximity scoring. Valid values:
positive integers. Default: 0. Valid for: dismax.
explicitPhraseSlop: An integer value that specifies
how much a match can deviate from the search phrase when the phrase is
enclosed in double quotes in the search string. (Phrases that exceed
this proximity distance are not considered a match.) For example, to
specify a slop of three for dismax phrase queries, you would specify
"explicitPhraseSlop":3. Valid values: positive integers.
Default: 0. Valid for: dismax.
tieBreaker: When a term in the search string is
found in a document's field, a score is calculated for that field based
on how common the word is in that field compared to other documents. If
the term occurs in multiple fields within a document, by default only
the highest scoring field contributes to the document's overall score.
You can specify a tieBreaker value to enable the matches in
lower-scoring fields to contribute to the document's score. That way, if
two documents have the same max field score for a particular term, the
score for the document that has matches in more fields will be higher.
The formula for calculating the score with a tieBreaker is (max field score) + (tieBreaker) * (sum of the scores for the rest of the matching fields).
Set tieBreaker to 0 to disregard all but the highest
scoring field (pure max): "tieBreaker":0. Set to 1 to sum
the scores from all fields (pure sum): "tieBreaker":1.
Valid values: 0.0 to 1.0. Default: 0.0. Valid for:
dismax.
|
queryParser |
Specifies which query parser to use to process the request. If
queryParser is not specified, Amazon CloudSearch uses the
simple query parser.
Amazon CloudSearch supports four query parsers:
simple: perform simple searches of text
and text-array fields. By default, the simple
query parser searches all text and text-array
fields. You can specify which fields to search by with the
queryOptions parameter. If you prefix a search term with a
plus sign (+) documents must contain the term to be considered a match.
(This is the default, unless you configure the default operator with the
queryOptions parameter.) You can use the -
(NOT), | (OR), and * (wildcard) operators to
exclude particular terms, find results that match any of the specified
terms, or search for a prefix. To search for a phrase rather than
individual terms, enclose the phrase in double quotes. For more
information, see Searching
for Text in the Amazon CloudSearch Developer
Guide.
structured: perform advanced searches by combining
multiple expressions to define the search criteria. You can also search
within particular fields, search for values and ranges of values, and
use advanced options such as term boosting, matchall, and
near. For more information, see Constructing
Compound Queries in the Amazon CloudSearch Developer
Guide.
lucene: search using the Apache Lucene query parser
syntax. For more information, see Apache
Lucene Query Parser Syntax.
dismax: search using the simplified subset of the
Apache Lucene query parser syntax defined by the DisMax query parser.
For more information, see DisMax Query Parser Syntax.
|
return |
Specifies the field and expression values to include in the
response. Multiple fields or expressions are specified as a
comma-separated list. By default, a search response includes all return
enabled fields (_all_fields). To
return only the document IDs for the matching documents, specify _no_fields. To retrieve the relevance
score calculated for each document, specify _score. |
size |
Specifies the maximum number of search hits to include in the
response. |
sort |
Specifies the fields or custom expressions to use to sort the
search results. Multiple fields or expressions are specified as a
comma-separated list. You must specify the sort direction
(asc or desc) for each field; for example,
year desc,title asc. To use a
field to sort results, the field must be sort-enabled in the domain
configuration. Array type fields cannot be used for sorting. If no
sort parameter is specified, results are sorted by their
default relevance scores in descending order: _score desc. You can also sort by
document ID (_id asc) and version
(_version desc).
For more information, see Sorting
Results in the Amazon CloudSearch Developer Guide. |
start |
Specifies the offset of the first search hit you want to return.
Note that the result set is zero-based; the first result is at index 0.
You can specify either the start or cursor
parameter in a request, they are mutually exclusive.
For more information, see Paginating
Results in the Amazon CloudSearch Developer Guide. |
stats |
Specifies one or more fields for which to get statistics
information. Each specified field must be facet-enabled in the domain
configuration. The fields are specified in JSON using the form:
{"FIELD-A":{},"FIELD-B":{}}
There are currently no options supported for statistics. |