Data Export By a User Without Required Permissions

gs_dump and gs_dumpall use -U to specify the user that performs the export. If the specified user does not have the required permissions, data cannot be exported. In this case, you need to assign the permission to a user who does not have the permission, and then set the -role parameter in the export command to specify the role with the permission. Then, gs_dump or gs_dumpall uses the -role parameter to specify a role to export data.

Procedure

1. Log in as the OS user omm to the primary node of the database.

2. Use gs_dump to export data of the human_resource database.

   User jack does not have the permissions to export data of the human_resource database and the role role1 has this permission. To export data of the human_resource database, you need to assign the permission of role1 to jack and set -role to role1 in the export command. The exported files are in .tar format.

   gs_dump -U jack -f /home/omm/backup/MPPDB_backup.tar -p 8000 human_resource --role role1 --rolepassword  abc@1234 -F t
   Password:

   Table 1 Common parameters

   Parameter	Description	Example Value
   -U	Username for database connection.	-U jack
   -W	User password for database connection. - This parameter is not required for database administrators if the trust policy is used for authentication. - If you connect to the database without specifying this parameter and you are not a database administrator, you will be prompted to enter the password.	-W Bigdata@123
   -f	Folder to store exported files. If this parameter is not specified, the exported files are stored in the standard output.	-f /home/omm/backup/MPPDB_backup.tar
   -p	TCP port or local Unix-domain socket file extension on which the server is listening for connections.	-p 8000
   dbname	Name of the database to export.	human_resource
   -role	Role name for the export operation. After this parameter is set, the SET ROLE command will be issued after gs_dump or gs_dumpall connects to the database. It is useful when the user specified by -U does not have the permissions required by gs_dump or gs_dumpall. This parameter allows you to switch to a role with the required permissions.	-r role1
   -rolepassword	Role password.	-rolepassword abc@1234
   -F	Select the format of file to export. The values of -F are as follows: - p: plaintext - c: custom - d: directory - t: .tar	-F t

   For details about other parameters, see "Tool Reference > Server Tools > gs_dump" or "gs_dumpall" in the Reference Guide.

Examples

Example 1: User jack does not have the permissions required to export data of the human_resource database using gs_dump and the role role1 has the permissions. To export data of the human_resource database, you can set -role to role1 in the gs_dump command. The exported files are in .tar format.

$ human_resource=# CREATE USER jack IDENTIFIED BY "1234@abc";
CREATE ROLE
human_resource=# GRANT role1 TO jack;
GRANT ROLE

$ gs_dump -U jack -f /home/omm/backup/MPPDB_backup11.tar -p 8000 human_resource --role role1 --rolepassword abc@1234 -F t
Password:
gs_dump[port='8000'][human_resource][2017-07-21 16:21:10]: dump database human_resource successfully
gs_dump[port='8000'][human_resource][2017-07-21 16:21:10]: total time: 4239  ms

Example 2: User jack does not have the permissions required to export the public schema using gs_dump and the role role1 has the permissions. To export the public schema, you can set -role to role1 in the gs_dump command. The exported files are in .tar format.

$ human_resource=# CREATE USER jack IDENTIFIED BY "1234@abc";
CREATE ROLE
human_resource=# GRANT role1 TO jack;
GRANT ROLE

$ gs_dump -U jack -f /home/omm/backup/MPPDB_backup12.tar -p 8000 human_resource -n public --role role1 --rolepassword abc@1234 -F t
Password:
gs_dump[port='8000'][human_resource][2017-07-21 16:21:10]: dump database human_resource successfully
gs_dump[port='8000'][human_resource][2017-07-21 16:21:10]: total time: 3278  ms

Example 3: User jack does not have the permissions required to export all databases in a cluster using gs_dumpall and the role role1 (cluster administrator) has the permissions. To export all the databases, you can set -role to role1 in the gs_dumpall command. The exported files are in text format.

$ human_resource=# CREATE USER jack IDENTIFIED BY "1234@abc";
CREATE ROLE
human_resource=# GRANT role1 TO jack;
GRANT ROLE

$ gs_dumpall -U jack -f /home/omm/backup/MPPDB_backup.sql -p 8000 --role role1 --rolepassword abc@1234
Password:
gs_dumpall[port='8000'][human_resource][2018-11-14 17:26:18]: dumpall operation successful
gs_dumpall[port='8000'][human_resource][2018-11-14 17:26:18]: total time: 6437  ms