Help Center/ MapReduce Service/ Component Operation Guide (LTS) (Ankara Region)/ Using IoTDB/ IoTDB Data Import and Export/ Importing IoTDB Data
Updated on 2024-11-29 GMT+08:00
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Importing IoTDB Data

Scenario

This section describes how to use import-csv.sh to import data in CSV format to IoTDB.

Prerequisites

  • The client has been installed. For example, the installation directory is /opt/client. The client directory in the following operations is only an example. Change it based on the actual installation directory onsite.
  • Service component users have been created by the MRS cluster administrator. In security mode, machine-machine users need to download the keytab file.. A human-machine user must change the password upon the first login.
  • By default, SSL is enabled on the server. You have generated the truststore.jks certificate by following the instructions provided in Using the IoTDB Client and copied it to the Client installation directory/IoTDB/iotdb/conf directory.

Procedure

  1. Prepare a CSV file named example-filename.csv on the local PC with the following content: 
    Time,root.fit.d1.s1,root.fit.d1.s2,root.fit.d2.s1,root.fit.d2.s3,root.fit.p.s1
1,100,hello,200,300,400
2,500,world,600,700,800
3,900,"hello, \"world\"",1000,1100,1200

    Before importing data, pay attention to the following:

    • The data to be imported cannot contain spaces. Otherwise, the data import fails. In this case, you need to check the type of the data to be imported.
    • Data that contains commas (,) must be enclosed in single or double quotation marks. For example, hello,world is changed to "hello,world".
    • Quotation marks ("") in the data must be replaced with the escape character \". For example, "world" is changed to \"world\".
    • Single quotation marks (') in the data must be replaced with the escape character \'. For example, 'world' will be changed to \'world\'.
    • If the data to be imported is time, the format is yyyy-MM-dd'T'HH:mm:ss, yyy-MM-dd HH:mm:ss or yyyy-MM-dd'T'HH:mm:ss.SSSZ, for example, 2022-02-28T11:07:00, 2022-02-28T11:07:00, or 2022-02-28T11:07:00.000Z.
  2. Use WinSCP to import the CSV file to the directory of the node where the client is installed, for example, /opt/client/IoTDB/iotdb/sbin.
  3. Log in to the node where the client is installed as the client installation user.
  4. Run the following command to switch to the client installation directory:

    cd /opt/client

  5. Run the following command to configure environment variables:

    source bigdata_env

  6. (Optional) Perform this step to authenticate the current user if Kerberos authentication is enabled for the cluster. If Kerberos authentication is not enabled, skip this step.

    kinit Component service user

  7. Run the following command to switch to the directory where the IoTDB client running script is stored:

    cd /opt/client/IoTDB/iotdb/sbin

  8. If Kerberos authentication is disabled for the cluster (the cluster is in normal mode), invoke the alter-cli-password.sh script to change the default password of the default user root.

    sh alter-cli-password.sh IP address of the IoTDBServer instance RPC port number

    • The default RPC port number of IoTDBServer is 22260, which can be configured in the IOTDB_SERVER_RPC_PORT parameter.
    • Obtain the default password of user root from the system administrator.
  9. Run the following command to log in to the client:

    ./start-cli.sh -h Service IP address of the IoTDBServer instance node -p IoTDBServer RPC port

    • You can log in to FusionInsight Manager and choose Cluster > Services > IoTDB > Instance to view the service IP address of the IoTDBServer instance node.
    • The default RPC port number is 22260. To obtain the port number, choose Cluster > Services > IoTDB, click Configurations then All Configurations, and search for IOTDB_SERVER_RPC_PORT.
    • If Kerberos authentication is disabled for the cluster (the cluster is in normal mode), use the default user root to log in to the IoTDB client.

    After you run this command, specify the service username as required.

    • To specify the service username, enter yes and enter the service username and password as prompted.

    • If you will not specify the service username, enter no. In this case, you will perform subsequent operations as the user in 6.

    • If you enter other information, you will log out.

  10. (Optional) Create metadata.
    IoTDB has the capability of type inference, so it is not necessary to create metadata before data import. However, it is recommended that you create metadata before using the CSV tool to import data, because this avoids unnecessary type conversion errors. The commands are as follows: 
    SET STORAGE GROUP TO root.fit.d1;
SET STORAGE GROUP TO root.fit.d2;
SET STORAGE GROUP TO root.fit.p;
CREATE TIMESERIES root.fit.d1.s1 WITH DATATYPE=INT32,ENCODING=RLE;
CREATE TIMESERIES root.fit.d1.s2 WITH DATATYPE=TEXT,ENCODING=PLAIN;
CREATE TIMESERIES root.fit.d2.s1 WITH DATATYPE=INT32,ENCODING=RLE;
CREATE TIMESERIES root.fit.d2.s3 WITH DATATYPE=INT32,ENCODING=RLE;
CREATE TIMESERIES root.fit.p.s1 WITH DATATYPE=INT32,ENCODING=RLE;
  11. Run the following command to exit the client:

    quit;

  12. Run the following command to switch to the directory where the import-csv.sh script is stored:

    cd /opt/client/IoTDB/iotdb/tools

  13. Run the following command to run import-csv.sh and import the example-filename.csv file:

    ./import-csv.sh -h Service IP address of the IoTDBServer instance -pIoTDBServer RPC port -f example-filename.csv

    Enter the service username and password in interactive mode as prompted. If information in the following figure is displayed, the CSV file is imported:

  14. Verify data consistency.
    1. Run the following command to switch to the directory where the IoTDB client running script is stored:

      cd /opt/client/IoTDB/iotdb/sbin

    2. Log in to the IoTDB client by referring to 9. Run SQL statements to query data and compare the data with that in the 1 file.
    3. Check whether the imported data is consistent with the data in the 1. If they are, the import is successful.

      Run the following command to check the imported data:

      SELECT * FROM root.fit.**;

      • To prevent security risks, you are advised to import CSV files in interactive mode.
      • You can also import CSV files by running the ./import-csv.sh -h Service IP address of the IoTDBServer instance -p IoTDBServer RPC port -u Service username -pw Service user password-f example-filename.csv command.

        If information in the following figure is displayed, the CSV file is imported.

      • If nanosecond (ns) time precision is enabled for the IoTDB on the server, the -tp ns parameter needs to be added when the client imports data with the nanosecond timestamp. To check whether nanosecond time precision is enabled for a cluster, log in to FusionInsight Manager, choose Cluster > Configurations > All Non-default Values, and search for timestamp_precision.