opensearch-docs-cn/_search-plugins/sql/sql-full-text.md

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---
layout: default
title: Full-Text Search
parent: SQL
nav_order: 8
---
# Full-text search
Use SQL commands for full-text search. The SQL plugin supports a subset of the full-text queries available in OpenSearch.
To learn about full-text queries in OpenSearch, see [Full-text queries]({{site.url}}{{site.baseurl}}/opensearch/query-dsl/full-text/).
## Match
Use the `match` command to search documents that match a `string`, `number`, `date`, or `boolean` value for a given field.
### Syntax
```sql
match(field_expression, query_expression[, option=<option_value>]*)
```
You can specify the following options:
- `analyzer`
- `auto_generate_synonyms_phrase`
- `fuzziness`
- `max_expansions`
- `prefix_length`
- `fuzzy_transpositions`
- `fuzzy_rewrite`
- `lenient`
- `operator`
- `minimum_should_match`
- `zero_terms_query`
- `boost`
*Example 1*: Search the `message` field:
```json
GET my_index/_search
{
"query": {
"match": {
"message": "this is a test"
}
}
}
```
SQL query:
```sql
SELECT message FROM my_index WHERE match(message, "this is a test")
```
*Example 2*: Search the `message` field with the `operator` parameter:
```json
GET my_index/_search
{
"query": {
"match": {
"message": {
"query": "this is a test",
"operator": "and"
}
}
}
}
```
SQL query:
```sql
SELECT message FROM my_index WHERE match(message, "this is a test", operator=and)
```
*Example 3*: Search the `message` field with the `operator` and `zero_terms_query` parameters:
```json
GET my_index/_search
{
"query": {
"match": {
"message": {
"query": "to be or not to be",
"operator": "and",
"zero_terms_query": "all"
}
}
}
}
```
SQL query:
```sql
SELECT message FROM my_index WHERE match(message, "this is a test", operator=and, zero_terms_query=all)
```
To search for text in a single field, use `MATCHQUERY` or `MATCH_QUERY` functions.
Pass in your search query and the field name that you want to search against.
```sql
SELECT account_number, address
FROM accounts
WHERE MATCH_QUERY(address, 'Holmes')
```
Alternate syntax:
```sql
SELECT account_number, address
FROM accounts
WHERE address = MATCH_QUERY('Holmes')
```
| account_number | address
:--- | :---
1 | 880 Holmes Lane
## Multi match
To search for text in multiple fields, use `MULTI_MATCH`, `MULTIMATCH`, or `MULTIMATCHQUERY` functions.
For example, search for `Dale` in either the `firstname` or `lastname` fields:
```sql
SELECT firstname, lastname
FROM accounts
WHERE MULTI_MATCH('query'='Dale', 'fields'='*name')
```
| firstname | lastname
:--- | :---
Dale | Adams
## Query string
To split text based on operators, use the `QUERY` function.
```sql
SELECT account_number, address
FROM accounts
WHERE QUERY('address:Lane OR address:Street')
```
| account_number | address
:--- | :---
1 | 880 Holmes Lane
6 | 671 Bristol Street
13 | 789 Madison Street
The `QUERY` function supports logical connectives, wildcard, regex, and proximity search.
## Match phrase
To search for exact phrases, use `MATCHPHRASE`, `MATCH_PHRASE`, or `MATCHPHRASEQUERY` functions.
```sql
SELECT account_number, address
FROM accounts
WHERE MATCH_PHRASE(address, '880 Holmes Lane')
```
| account_number | address
:--- | :---
1 | 880 Holmes Lane
## Score query
To return a relevance score along with every matching document, use `SCORE`, `SCOREQUERY`, or `SCORE_QUERY` functions.
You need to pass in two arguments. The first is the `MATCH_QUERY` expression. The second is an optional floating point number to boost the score (default value is 1.0).
```sql
SELECT account_number, address, _score
FROM accounts
WHERE SCORE(MATCH_QUERY(address, 'Lane'), 0.5) OR
SCORE(MATCH_QUERY(address, 'Street'), 100)
ORDER BY _score
```
| account_number | address | score
:--- | :--- | :---
1 | 880 Holmes Lane | 0.5
6 | 671 Bristol Street | 100
13 | 789 Madison Street | 100