InfluxDB Line Protocol

Introduction

In the InfluxDB Line protocol format, a single line of text is used to represent one row of data. Each line contains 4 parts as shown below.

measurement,tag_set field_set timestamp

• measurement will be used as the name of the STable
• tag_set will be used as tags, with format like <tag_key>=<tag_value>,<tag_key>=<tag_value>
• field_setwill be used as data columns, with format like <field_key>=<field_value>,<field_key>=<field_value>
• timestamp is the primary key timestamp corresponding to this row of data

For example:

meters,location=California.LoSangeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500

note

• All the data in tag_set will be converted to nchar type automatically .
• Each data in field_set must be self-descriptive for its data type. For example 1.2f32 means a value 1.2 of float type. Without the "f" type suffix, it will be treated as type double.
• Multiple kinds of precision can be used for the timestamp field. Time precision can be from nanosecond (ns) to hour (h).

For more details please refer to InfluxDB Line Protocol and TDengine Schemaless

Examples

Java

package com.taos.example;

import com.taosdata.jdbc.SchemalessWriter;
import com.taosdata.jdbc.enums.SchemalessProtocolType;
import com.taosdata.jdbc.enums.SchemalessTimestampType;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class LineProtocolExample {
    // format: measurement,tag_set field_set timestamp
    private static String[] lines = {
            "meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249000", // micro
                                                                                                              // seconds
            "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500",
            "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249300",
            "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611249800",
    };

    private static Connection getConnection() throws SQLException {
        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
        return DriverManager.getConnection(jdbcUrl);
    }

    private static void createDatabase(Connection conn) throws SQLException {
        try (Statement stmt = conn.createStatement()) {
            // the default precision is ms (millisecond), but we use us(microsecond) here.
            stmt.execute("CREATE DATABASE IF NOT EXISTS test PRECISION 'us'");
            stmt.execute("USE test");
        }
    }

    public static void main(String[] args) throws SQLException {
        try (Connection conn = getConnection()) {
            createDatabase(conn);
            SchemalessWriter writer = new SchemalessWriter(conn);
            writer.write(lines, SchemalessProtocolType.LINE, SchemalessTimestampType.MICRO_SECONDS);
        }
    }
}

view source code

Python

import taos
from taos import SmlProtocol, SmlPrecision

lines = ["meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249000",
         "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500",
         "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249300",
         "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611249800",
         ]


def get_connection():
    # create connection use firstEP in taos.cfg.
    return taos.connect()


def create_database(conn):
    # the default precision is ms (microsecond), but we use us(microsecond) here.
    conn.execute("CREATE DATABASE test precision 'us'")
    conn.execute("USE test")


def insert_lines(conn):
    affected_rows = conn.schemaless_insert(
        lines, SmlProtocol.LINE_PROTOCOL, SmlPrecision.MICRO_SECONDS)
    print(affected_rows)  # 8


if __name__ == '__main__':
    connection = get_connection()
    try:
        create_database(connection)
        insert_lines(connection)
    finally:
        connection.close()

view source code

Go

package main

import (
	"fmt"

	"github.com/taosdata/driver-go/v2/af"
)

func prepareDatabase(conn *af.Connector) {
	_, err := conn.Exec("CREATE DATABASE test")
	if err != nil {
		panic(err)
	}
	_, err = conn.Exec("USE test")
	if err != nil {
		panic(err)
	}
}

func main() {
	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
	if err != nil {
		fmt.Println("fail to connect, err:", err)
	}
	defer conn.Close()
	prepareDatabase(conn)
	var lines = []string{
		"meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
		"meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
		"meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
		"meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250",
	}

	err = conn.InfluxDBInsertLines(lines, "ms")
	if err != nil {
		fmt.Println("insert error:", err)
	}
}

view source code

Rust

use libtaos::schemaless::*;
use libtaos::*;

fn main() {
    let taos = TaosCfg::default().connect().expect("fail to connect");
    taos.raw_query("CREATE DATABASE test").unwrap();
    taos.raw_query("USE test").unwrap();
    let lines = ["meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
    "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
    "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
    "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250"];
    let affected_rows = taos
        .schemaless_insert(
            &lines,
            TSDB_SML_LINE_PROTOCOL,
            TSDB_SML_TIMESTAMP_MILLISECONDS,
        )
        .unwrap();
    println!("affected_rows={}", affected_rows);
}

// run with:  cargo run --example influxdb_line_example

view source code

Node.js

const taos = require("td2.0-connector");

const conn = taos.connect({
  host: "localhost",
});

const cursor = conn.cursor();

function createDatabase() {
  cursor.execute("CREATE DATABASE test");
  cursor.execute("USE test");
}

function insertData() {
  const lines = [
    "meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
    "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
    "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
    "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250",
  ];
  cursor.schemalessInsert(
    lines,
    taos.SCHEMALESS_PROTOCOL.TSDB_SML_LINE_PROTOCOL,
    taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_MILLI_SECONDS
  );
}

try {
  createDatabase();
  insertData();
} finally {
  cursor.close(); 
  conn.close();
}

view source code

C#

using TDengineDriver;

namespace TDengineExample
{
    internal class InfluxDBLineExample
    {
        static void Main()
        {
            IntPtr conn = GetConnection();
            PrepareDatabase(conn);
            string[] lines = {
                "meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
                "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
                "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
                "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250"
            };
            IntPtr res = TDengine.SchemalessInsert(conn, lines, lines.Length, (int)TDengineSchemalessProtocol.TSDB_SML_LINE_PROTOCOL, (int)TDengineSchemalessPrecision.TSDB_SML_TIMESTAMP_MILLI_SECONDS);
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("SchemalessInsert failed since " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
            else
            {
                int affectedRows = TDengine.AffectRows(res);
                Console.WriteLine($"SchemalessInsert success, affected {affectedRows} rows");
            }
            TDengine.FreeResult(res);
            ExitProgram(conn, 0);

        }
        static IntPtr GetConnection()
        {
            string host = "localhost";
            short port = 6030;
            string username = "root";
            string password = "taosdata";
            string dbname = "";
            var conn = TDengine.Connect(host, username, password, dbname, port);
            if (conn == IntPtr.Zero)
            {
                Console.WriteLine("Connect to TDengine failed");
                TDengine.Cleanup();
                Environment.Exit(1);
            }
            else
            {
                Console.WriteLine("Connect to TDengine success");
            }
            return conn;
        }

        static void PrepareDatabase(IntPtr conn)
        {
            IntPtr res = TDengine.Query(conn, "CREATE DATABASE test");
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("failed to create database, reason: " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
            res = TDengine.Query(conn, "USE test");
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("failed to change database, reason: " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
        }

        static void ExitProgram(IntPtr conn, int exitCode)
        {
            TDengine.Close(conn);
            TDengine.Cleanup();
            Environment.Exit(exitCode);
        }
    }

}

view source code

C

int main() {
  TAOS *taos = taos_connect("localhost", "root", "taosdata", "", 0);
  if (taos == NULL) {
    printf("failed to connect to server\n");
    exit(EXIT_FAILURE);
  }
  executeSQL(taos, "DROP DATABASE IF EXISTS test");
  executeSQL(taos, "CREATE DATABASE test");
  executeSQL(taos, "USE test");
  char     *lines[] = {"meters,location=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
                   "meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
                   "meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
                   "meters,location=California.LosAngeles,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250"};
  TAOS_RES *res = taos_schemaless_insert(taos, lines, 4, TSDB_SML_LINE_PROTOCOL, TSDB_SML_TIMESTAMP_MILLI_SECONDS);
  if (taos_errno(res) != 0) {
    printf("failed to insert schema-less data, reason: %s\n", taos_errstr(res));
  } else {
    int affectedRows = taos_affected_rows(res);
    printf("successfully inserted %d rows\n", affectedRows);
  }
  taos_free_result(res);
  taos_close(taos);
  taos_cleanup();
}
// output:
// successfully inserted 4 rows

view source code