opensearch-docs-cn/docs/sql/index.md

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---
layout: default
title: SQL
nav_order: 38
has_children: true
has_toc: false
---
# SQL
OpenSearch SQL lets you write queries in SQL rather than the [OpenSearch query domain-specific language (DSL)](../opensearch/full-text). If you're already familiar with SQL and don't want to learn the query DSL, this feature is a great option.
## Workbench
The easiest way to get familiar with the SQL plugin is to use **SQL Workbench** in OpenSearch Dashboards to test various queries. To learn more, see [Workbench](workbench/).
![OpenSearch Dashboards SQL UI plugin](../images/sql.png)
## REST API
To use the SQL plugin with your own applications, send requests to `_opensearch/_sql`:
```json
POST _opensearch/_sql
{
"query": "SELECT * FROM my-index LIMIT 50"
}
```
Heres how core SQL concepts map to OpenSearch:
SQL | OpenSearch
:--- | :---
Table | Index
Row | Document
Column | Field
You can query multiple indices by listing them or using wildcards:
```json
POST _opensearch/_sql
{
"query": "SELECT * FROM my-index1,myindex2,myindex3 LIMIT 50"
}
POST _opensearch/_sql
{
"query": "SELECT * FROM my-index* LIMIT 50"
}
```
For a sample [curl](https://curl.haxx.se/) command, try:
```bash
curl -XPOST https://localhost:9200/_opensearch/_sql -u 'admin:admin' -k -H 'Content-Type: application/json' -d '{"query": "SELECT * FROM opensearch_dashboards_sample_data_flights LIMIT 10"}'
```
By default, queries return data in JDBC format, but you can also return data in standard OpenSearch JSON, CSV, or raw formats:
```json
POST _opensearch/_sql?format=json|csv|raw
{
"query": "SELECT * FROM my-index LIMIT 50"
}
```
See the rest of this guide for detailed information on request parameters, settings, supported operations, tools, and more.
## Contributing
To get involved and help us improve the SQL plugin, see the [development guide](https://github.com/opensearch-project/sql/blob/master/docs/developing.rst) for instructions on setting up your development environment and building the project.