Help Center/ GaussDB/ Developer Guide(Distributed_2.x)/ Importing Data/ Importing Data in Parallel Using Foreign Tables/ Examples/ Example 2: Importing Data in Shared Mode
Updated on 2024-10-14 GMT+08:00
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Example 2: Importing Data in Shared Mode

  1. Prepare for data import.
    This section assumes that a source data file foreign_tpcds_reasons.dat.0 in text format is stored in the /input_data directory on the 192.168.0.90 server.
    1. Configure the NFS service on the data server. For details, see SUSE DOC: Administration Guide – Configuring NFS Server.

      The security of the NFS service and data transmission is ensured by users. You are advised to use the NFS service in a trusted domain.

    2. Start the NFS service on the data server. 
      service nfs start
    3. Log in as a common user to each server where GaussDB DNs reside, create the /input_data directory on each server, and mount each data server storing source data files to this directory. 
      cd /input_data
mount -t nfs 192.168.0.90:/input_data /input_data
  2. Log in as the OS user omm to the host where the CN is located.
  3. Run the following command to connect to the database: 
    gsql -d postgres -p 8000

    postgres is the name of the database, and 8000 is the port number of the CN.

    If information similar to the following is displayed, the connection succeeds:

    gsql((GaussDB Kernel VxxxRxxxCxx build f521c606) compiled at 2021-09-16 14:55:22 commit 2935 last mr 6385 release)
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.

openGauss=#
  4. Create the target table reasons. 
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    openGauss=# CREATE TABLE reasons
(
  r_reason_sk integer not null,
  r_reason_id char(16) not null,
  r_reason_desc char(100)
);
  5. Create the foreign table foreign_tpcds_reasons for the source data. 
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    openGauss=# CREATE FOREIGN TABLE foreign_tpcds_reasons
(
  r_reason_sk integer not null,
  r_reason_id char(16) not null,
  r_reason_desc char(100)
) SERVER gsmpp_server OPTIONS (location 'file:///input_data/foreign_tpcds_reasons.dat.0', format 'TEXT', mode 'shared', delimiter E'\x20',  NULL '');
  6. Import data to the reasons table. 
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    openGauss=# INSERT INTO reasons SELECT * FROM foreign_tpcds_reasons;
Parent topic: Examples