CREATE SERVER

Description

Creates a foreign server.

A foreign server stores OBS server information or other homogeneous cluster information.

Precautions

Only a system administrator and users with permission to use a specified FOREIGN DATA WRAPPER can create a foreign server. The authorization syntax is as follows:

GRANT USAGE ON FOREIGN DATA WRAPPER fdw_name TO username

fdw_name is the name of the FOREIGN DATA WRAPPER, and username is the name of the user creating a foreign server.

When multi-layer quotation marks are used for sensitive columns (such as password and secret_access_key) in OPTIONS, the semantics is different from that in the scenario where quotation marks are not used. Therefore, sensitive columns are not identified for anonymization.

Syntax

    
         CREATE SERVER server_name 
    FOREIGN DATA WRAPPER fdw_name
    OPTIONS ( { option_name ' value ' } [, ...] ) ;

Parameters

server_name
Specifies the server name.

Value range: a string containing no more than 63 characters
FOREIGN DATA WRAPPER fdw_name
Specifies the name of the foreign data wrapper.

Value range: fdw_name is the data wrapper created by the system during database initialization. Currently, fdw_name can only be gc_fdw for other homogeneous clusters. You can also create dist_fdw, file_fdw, and log_fdw.
OPTIONS ( { option_name ' value ' } [, ...] )
Specifies the parameters for the foreign server. The detailed parameter description is as follows:
- encrypt
  Specifies whether data is encrypted. This parameter is available only when type is OBS. The default value is on.
  
  Value range:
  - on indicates that data is encrypted and HTTPS is used for communication.
  - off indicates that data is not encrypted and HTTP is used for communication.
- access_key
  Specifies the access key (AK) (obtained by users from the OBS console) used for the OBS access protocol. When you create a foreign table, the AK value is encrypted and saved to the metadata table of the database. This parameter is available only when type is set to OBS.
- secret_access_key
  Specifies the secret key (SK) value (obtained by users from the OBS console) used for the OBS access protocol. When you create a foreign table, the SK value is encrypted and saved to the metadata table of the database. This parameter is available only when type is set to OBS.

Examples

Create my_server, in which file_fdw is the built-in foreign data wrapper.

    
         -- Create my_server.
openGauss=# CREATE SERVER my_server FOREIGN DATA WRAPPER file_fdw;

-- Delete my_server.
openGauss=# DROP SERVER my_server;

You are advised to create another server in the homogeneous cluster, where gc_fdw is the foreign data wrapper in the database.

    
         -- Create a server.
openGauss=# CREATE SERVER server_remote FOREIGN DATA WRAPPER GC_FDW OPTIONS 
   (address '10.146.187.231:8000,10.180.157.130:8000' ,
  dbname 'test', 
  username 'test', 
  password 'xxxxxxxx'
);

-- Delete the server.
openGauss=# DROP SERVER server_remote;