Prefix query
Use the prefix query to search for terms that begin with a specific prefix. For example, the following query searches for documents in which the speaker field contains a term that starts with KING H:
GET shakespeare/_search
{
"query": {
"prefix": {
"speaker": "KING H"
}
}
}
To provide parameters, you can use a query equivalent to the preceding one with the following extended syntax:
GET shakespeare/_search
{
"query": {
"prefix": {
"speaker": {
"value": "KING H"
}
}
}
}
Parameters
The query accepts the name of the field (<field>) as a top-level parameter:
GET _search
{
"query": {
"prefix": {
"<field>": {
"value": "sample",
...
}
}
}
}
The <field> accepts the following parameters. All parameters except value are optional.
| Parameter | Data type | Description |
|---|---|---|
value | String | The term to search for in the field specified in <field>. |
case_insensitive | Boolean | If true, allows case-insensitive matching of the value with the indexed field values. Default is false (case sensitivity is determined by the field’s mapping). |
rewrite | String | Determines how OpenSearch rewrites and scores multi-term queries. Valid values are constant_score, scoring_boolean, constant_score_boolean, top_terms_N, top_terms_boost_N, and top_terms_blended_freqs_N. Default is constant_score. |
If search.allow_expensive_queries is set to false, prefix queries are not run. If index_prefixes is enabled, the search.allow_expensive_queries setting is ignored and an optimized query is built and run.