OpenSearch/docs/reference/mapping/params/position-increment-gap.asci...

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[[position-increment-gap]]
=== `position_increment_gap`
<<mapping-index,Analyzed>> text fields take term <<index-options,positions>>
into account, in order to be able to support
<<query-dsl-match-query-phrase,proximity or phrase queries>>.
When indexing text fields with multiple values a "fake" gap is added between
the values to prevent most phrase queries from matching across the values. The
size of this gap is configured using `position_increment_gap` and defaults to
`100`.
For example:
[source,console]
--------------------------------------------------
PUT my-index-000001/_doc/1
{
"names": [ "John Abraham", "Lincoln Smith"]
}
GET my-index-000001/_search
{
"query": {
"match_phrase": {
"names": {
"query": "Abraham Lincoln" <1>
}
}
}
}
GET my-index-000001/_search
{
"query": {
"match_phrase": {
"names": {
"query": "Abraham Lincoln",
"slop": 101 <2>
}
}
}
}
--------------------------------------------------
<1> This phrase query doesn't match our document which is totally expected.
<2> This phrase query matches our document, even though `Abraham` and `Lincoln`
are in separate strings, because `slop` > `position_increment_gap`.
The `position_increment_gap` can be specified in the mapping. For instance:
[source,console]
--------------------------------------------------
PUT my-index-000001
{
"mappings": {
"properties": {
"names": {
"type": "text",
"position_increment_gap": 0 <1>
}
}
}
}
PUT my-index-000001/_doc/1
{
"names": [ "John Abraham", "Lincoln Smith"]
}
GET my-index-000001/_search
{
"query": {
"match_phrase": {
"names": "Abraham Lincoln" <2>
}
}
}
--------------------------------------------------
<1> The first term in the next array element will be 0 terms apart from the
last term in the previous array element.
<2> The phrase query matches our document which is weird, but its what we asked
for in the mapping.