Intervals queryedit
Returns documents based on the order and proximity of matching terms.
The intervals query uses matching rules, constructed from a small set of
definitions. Theses rules are then applied to terms from a specified field.
The definitions produce sequences of minimal intervals that span terms in a body of text. These intervals can be further combined and filtered by parent sources.
Example requestedit
The following intervals search returns documents containing my
favorite food immediately followed by hot water or cold porridge in the
my_text field.
This search would match a my_text value of my favorite food is cold
porridge but not when it's cold my favorite food is porridge.
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"all_of" : {
"ordered" : true,
"intervals" : [
{
"match" : {
"query" : "my favorite food",
"max_gaps" : 0,
"ordered" : true
}
},
{
"any_of" : {
"intervals" : [
{ "match" : { "query" : "hot water" } },
{ "match" : { "query" : "cold porridge" } }
]
}
}
]
}
}
}
}
}
Top-level parameters for intervalsedit
match rule parametersedit
The match rule matches analyzed text.
-
query -
(Required, string) Text you wish to find in the provided
<field>. -
max_gaps -
(Optional, integer) Maximum number of positions between the matching terms. Terms further apart than this are not considered matches. Defaults to
-1.If unspecified or set to
-1, there is no width restriction on the match. If set to0, the terms must appear next to each other. -
ordered -
(Optional, boolean)
If
true, matching terms must appear in their specified order. Defaults tofalse. -
analyzer -
(Optional, string) analyzer used to analyze terms in the
query. Defaults to the top-level<field>'s analyzer. -
filter - (Optional, interval filter rule object) An optional interval filter.
all_of rule parametersedit
The all_of rule returns matches that span a combination of other rules.
-
intervals - (Required, array of rule objects) An array of rules to combine. All rules must produce a match in a document for the overall source to match.
-
max_gaps -
(Optional, integer) Maximum number of positions between the matching terms. Intervals produced by the rules further apart than this are not considered matches. Defaults to
-1.If unspecified or set to
-1, there is no width restriction on the match. If set to0, the terms must appear next to each other. -
ordered -
(Optional, boolean) If
true, intervals produced by the rules should appear in the order in which they are specified. Defaults tofalse. -
filter - (Optional, interval filter rule object) Rule used to filter returned intervals.
any_of rule parametersedit
The any_of rule returns intervals produced by any of its sub-rules.
-
intervals - (Required, array of rule objects) An array of rules to match.
-
filter - (Optional, interval filter rule object) Rule used to filter returned intervals.
filter rule parametersedit
The filter rule returns intervals based on a query. See
Filter example for an example.
-
after -
(Optional, query object) Query used to return intervals that follow an interval
from the
filterrule. -
before -
(Optional, query object) Query used to return intervals that occur before an
interval from the
filterrule. -
contained_by -
(Optional, query object) Query used to return intervals contained by an interval
from the
filterrule. -
containing -
(Optional, query object) Query used to return intervals that contain an interval
from the
filterrule. -
not_contained_by -
(Optional, query object) Query used to return intervals that are not
contained by an interval from the
filterrule. -
not_containing -
(Optional, query object) Query used to return intervals that do not contain
an interval from the
filterrule. -
not_overlapping -
(Optional, query object) Query used to return intervals that do not overlap
with an interval from the
filterrule. -
overlapping -
(Optional, query object) Query used to return intervals that overlap with an
interval from the
filterrule. -
script -
(Optional, script object) Script used to return
matching documents. This script must return a boolean value,
trueorfalse. See Script filters for an example.
Notesedit
Filter exampleedit
The following search includes a filter rule. It returns documents that have
the words hot and porridge within 10 positions of each other, without the
word salty in between:
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"match" : {
"query" : "hot porridge",
"max_gaps" : 10,
"filter" : {
"not_containing" : {
"match" : {
"query" : "salty"
}
}
}
}
}
}
}
}
Script filtersedit
You can use a script to filter intervals based on their start position, end
position, and internal gap count. The following filter script uses the
interval variable with the start, end, and gaps methods:
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"match" : {
"query" : "hot porridge",
"filter" : {
"script" : {
"source" : "interval.start > 10 && interval.end < 20 && interval.gaps == 0"
}
}
}
}
}
}
}
Minimizationedit
The intervals query always minimizes intervals, to ensure that queries can
run in linear time. This can sometimes cause surprising results, particularly
when using max_gaps restrictions or filters. For example, take the
following query, searching for salty contained within the phrase hot
porridge:
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"match" : {
"query" : "salty",
"filter" : {
"contained_by" : {
"match" : {
"query" : "hot porridge"
}
}
}
}
}
}
}
}
This query does not match a document containing the phrase hot porridge is
salty porridge, because the intervals returned by the match query for hot
porridge only cover the initial two terms in this document, and these do not
overlap the intervals covering salty.
Another restriction to be aware of is the case of any_of rules that contain
sub-rules which overlap. In particular, if one of the rules is a strict
prefix of the other, then the longer rule can never match, which can
cause surprises when used in combination with max_gaps. Consider the
following query, searching for the immediately followed by big or big bad,
immediately followed by wolf:
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"all_of" : {
"intervals" : [
{ "match" : { "query" : "the" } },
{ "any_of" : {
"intervals" : [
{ "match" : { "query" : "big" } },
{ "match" : { "query" : "big bad" } }
] } },
{ "match" : { "query" : "wolf" } }
],
"max_gaps" : 0,
"ordered" : true
}
}
}
}
}
Counter-intuitively, this query does not match the document the big bad
wolf, because the any_of rule in the middle only produces intervals
for big - intervals for big bad being longer than those for big, while
starting at the same position, and so being minimized away. In these cases,
it’s better to rewrite the query so that all of the options are explicitly
laid out at the top level:
POST _search
{
"query": {
"intervals" : {
"my_text" : {
"any_of" : {
"intervals" : [
{ "match" : {
"query" : "the big bad wolf",
"ordered" : true,
"max_gaps" : 0 } },
{ "match" : {
"query" : "the big wolf",
"ordered" : true,
"max_gaps" : 0 } }
]
}
}
}
}
}