homework-jianmu/docs/en/08-develop/03-insert-data/50-opentsdb-json.mdx

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---
title: OpenTSDB JSON Protocol
sidebar_label: OpenTSDB JSON Protocol
description: This document describes how to insert data into TDengine using the OpenTSDB JSON protocol.
---
import Tabs from "@theme/Tabs";
import TabItem from "@theme/TabItem";
import JavaJson from "./_java_opts_json.mdx";
import PyJson from "./_py_opts_json.mdx";
import GoJson from "./_go_opts_json.mdx";
import RustJson from "./_rust_opts_json.mdx";
import NodeJson from "./_js_opts_json.mdx";
import CsJson from "./_cs_opts_json.mdx";
import CJson from "./_c_opts_json.mdx";
## Introduction
A JSON string is used in OpenTSDB JSON to represent one or more rows of data, for example: For example:
```json
[
{
"metric": "sys.cpu.nice",
"timestamp": 1346846400,
"value": 18,
"tags": {
"host": "web01",
"dc": "lga"
}
},
{
"metric": "sys.cpu.nice",
"timestamp": 1346846400,
"value": 9,
"tags": {
"host": "web02",
"dc": "lga"
}
}
]
```
Similar to OpenTSDB line protocol, `metric` will be used as the STable name, `timestamp` is the timestamp to be used, `value` represents the metric collected, `tags` are the tag sets.
Please refer to [OpenTSDB HTTP API](http://opentsdb.net/docs/build/html/api_http/put.html) for more details.
:::note
- In JSON protocol, strings will be converted to NCHAR type and numeric values will be converted to double type.
- The rule of table name
- The child table name is created automatically in a rule to guarantee its uniqueness.
- You can configure `smlAutoChildTableNameDelimiter` in taos.cfg to specify a delimiter between tag values as the table names. For example, you set `smlAutoChildTableNameDelimiter=-` in taos.cfg, when you insert `st,t0=cpu1,t1=4 c1=3 1626006833639000000`, the child table will be `cpu1-4`
- You can configure `smlChildTableName` in taos.cfg to specify a tag value as the table names if the tag value is unique globally. For example, if a tag is called `tname` and you set `smlChildTableName=tname` in taos.cfg, when you insert `st,tname=cpu1,t1=4 c1=3 1626006833639000000`, the child table `cpu1` will be created automatically. Note that if multiple rows have the same tname but different tag_set values, the tag_set of the first row is used to create the table and the others are ignored
:::
## Examples
<Tabs defaultValue="java" groupId="lang">
<TabItem label="Java" value="java">
<JavaJson />
</TabItem>
<TabItem label="Python" value="Python">
<PyJson />
</TabItem>
<TabItem label="Go" value="go">
<GoJson />
</TabItem>
<TabItem label="Node.js" value="node">
<NodeJson />
</TabItem>
<TabItem label="C#" value="csharp">
<CsJson />
</TabItem>
<TabItem label="C" value="c">
<CJson />
</TabItem>
</Tabs>
2 STables will be created automatically and each STable has 2 rows of data in the above sample code.
```cmd
taos> use test;
Database changed.
taos> show stables;
name |
=================================
meters_current |
meters_voltage |
Query OK, 2 row(s) in set (0.001954s)
taos> select * from `meters_current`;
_ts | _value | groupid | location |
===================================================================================================================
2022-03-28 09:56:51.249 | 10.300000000 | 2.000000000 | California.SanFrancisco |
2022-03-28 09:56:51.250 | 12.600000000 | 2.000000000 | California.SanFrancisco |
Query OK, 2 row(s) in set (0.004076s)
```
## Query Examples
If you want query the data of "tags": &lcub;"location": "California.LosAngeles", "groupid": 1&rcub;, here is the query SQL:
```sql
SELECT * FROM `meters_current` WHERE location = "California.LosAngeles" AND groupid = 3;
```