CREATE EXTERNAL MOUNT
Create an NFS mount for use with external tables.
CREATE EXTERNAL MOUNT [ IF NOT EXISTS ] 'reference_name'
AS 'fully_qualified_nfs_path'
[ WITH ( option value [, ...] ) ]
READONLY | WRITEONLY
You must be a superuser to run this command.
WITH
clause: GID <gid>
: Group ID to use when mounting and interacting with the NFS volumeUID <uid>
: User ID to use when mounting and interacting with the NFS volume
By default, the command runs a verification check that the NFS volume allows both read and
write access. If you want to limit this check to verifying read-only access or write-only
access, specify READONLY
or WRITEONLY
at the end of the
command (not as a WITH
option).
Read-only access to a mount will work for SELECT FROM EXTERNAL
(ybload
) operations; external table files can be selected from in
queries. Write-only access to a mount will work for CREATE EXTERNAL TABLE
(ybunload
) operations; external table files can be written and listed.
The command will either complete successfully or return an "Insufficient
permissions"
error.
ybload
logs for those
queries to a writable mount directory. You can use the logdir
option in
the CREATE EXTERNAL TABLE
command or the SELECT FROM
EXTERNAL
command to specify a writable mount directory. Examples
premdb=# create external mount '/qumulo/ext_db/' as
'nfs://qumulo:/data/bobrum/ext_db/'
with (gid 1234, uid 4567);
premdb=# drop external mount '/qumulo/ext_db/';
DROP EXTERNAL MOUNT
premdb=# create external mount '/qumulo/ext_db/' as
'nfs://qumulo:/data/bobrum/ext_db/'
with (gid 1234, uid 4567)
writeonly;