Append standard output using \o

Hello Norbert,

I found the following piece of Vertica documentation that may help:

http://my.vertica.com/docs/7.0.x/HTML/index.htm#Authoring/ProgrammersGuide/vsql/CommandLineOptions/o...

Please let me if this was of any assistance!

Thanks,
Rory

It was not. I'm looking to append to the file, such as:

echo '1' >> test.txt  echo '2' >> test.txt    cat test.txt  1  2

Hello Norbert,

Thanks for the update. I did some testing and it does appear that you can append to a file in the same database session, but you cannot append to the file after the database session is closed:

dbadmin=> \o test.txt
dbadmin=> select * from nodes;
dbadmin=> select * from system;
dbadmin=> \q
[dbadmin@rmckeon1 ~]$ cat test.txt
      node_name       |      node_id      | node_state | node_address | export_address |                         catalog_path                         | is_ephemeral
----------------------+-------------------+------------+--------------+----------------+--------------------------------------------------------------+--------------
 v_testdb_node0001 | 45035996273704980 | UP         | <IP Address> | <IP Address>  | /home/dbadmin/testdb/v_testdb_node0001_catalog/Catalog | f
 v_testdb_node0002 | 45035996273718962 | UP         | <IP Address> | <IP Address>  | /home/dbadmin/testdb/v_testdb_node0002_catalog/Catalog | f
 v_testdb_node0003 | 45035996273718966 | UP         | <IP Address> | <IP Address>  | /home/dbadmin/testdb/v_testdb_node0003_catalog/Catalog | f
(3 rows)

 current_epoch | ahm_epoch | last_good_epoch | refresh_epoch | designed_fault_tolerance | node_count | node_down_count | current_fault_tolerance | catalog_revision_number | wos_used_bytes | wos_row_count | ros_used_bytes | ros_row_count | total_used_bytes | total_row_count
---------------+-----------+-----------------+---------------+--------------------------+------------+-----------------+-------------------------+-------------------------+----------------+---------------+----------------+---------------+------------------+-----------------
           139 |       138 |             138 |            -1 |                        1 |          3 |               0 |                       1 |                     479 |              0 |             0 |           7454 |           290 |             7454 |             290
(1 row)


Then, I logged out of the database, logged back in, and then ran:

dbadmin=> \o test.txt
dbadmin=> select * from resource_pools;
dbadmin=> \q
[dbadmin@rmckeon1 ~]$ cat test.txt
      pool_id      |   name   | is_internal | memorysize | maxmemorysize | executionparallelism | priority | runtimepriority | runtimeprioritythreshold | queuetimeout | plannedconcurrency | maxconcurrency | runtimecap | singleinitiator | cpuaffinityset | cpuaffinitymode
-------------------+----------+-------------+------------+---------------+----------------------+----------+-----------------+--------------------------+--------------+--------------------+----------------+------------+-----------------+----------------+-----------------
 45035996273718864 | general  | t           |            | Special: 95%  | AUTO                 |        0 | MEDIUM          |                        2 |          300 | AUTO               |                |            | f               |                | ANY
 45035996273718866 | sysquery | t           | 64M        |               | AUTO                 |      110 | HIGH            |                        0 |          300 | AUTO               |                |            | f               |                | ANY
 45035996273718868 | sysdata  | t           | 100M       | 1G            |                      |          |                 |                          |              |                    |                |            |                 |                |
 45035996273718870 | wosdata  | t           | 0%         | 2G            |                      |          |                 |                          |              | AUTO               |                |            |                 |                |
 45035996273718872 | tm       | t           | 200M       |               | AUTO                 |      105 | MEDIUM          |                       60 |          300 | AUTO               |              3 |            | t               |                | ANY
 45035996273718874 | refresh  | t           | 0%         |               | AUTO                 |      -10 | MEDIUM          |                       60 |          300 | 4                  |                |            | t               |                | ANY
 45035996273718876 | recovery | t           | 0%         |               | AUTO                 |      107 | MEDIUM          |                       60 |          300 | AUTO               |              3 |            | t               |                | ANY
 45035996273718878 | dbd      | t           | 0%         |               | AUTO                 |        0 | MEDIUM          |                        0 |            0 | AUTO               |                |            | t               |                | ANY
 45035996273718960 | jvm      | t           | 0%         | 10%           | AUTO                 |        0 | MEDIUM          |                        2 |          300 | AUTO               |                |            | f               |                | ANY
(9 rows)


I will create a feature request to potentially have this added to a future release of the product.

Thanks,
Rory

I appreciate the answer. That's what I was looking for. Thank you!

Hello Norbert,

You're welcome. Take care!

Thanks,
Rory

Hi all,

Thanks Rory for following up on this limitation!  Hope you don't mind if I jump in briefly:

Norbert (and anyone else reading this), the following should function as a workaround:

\o | cat >> out.txt

It's not the most elegant approach, but it should work fine.

Adam

No problem at all - thanks Adam! I tested internally and this does work.

Thanks,
Rory

Instead of using \o alone, you can pipe the output to cat and then use >> to append the output.

For example:

twall@ubuntu:~$ vsql
Welcome to vsql, the Vertica Analytic Database interactive terminal.

Type:  \h or \? for help with vsql commands
       \g or terminate with semicolon to execute query
       \q to quit

twall=> \o | cat >> file.txt
twall=> select 1;
twall=> select 2;
twall=> \q
twall@ubuntu:~$ vsql
Welcome to vsql, the Vertica Analytic Database interactive terminal.

Type:  \h or \? for help with vsql commands
       \g or terminate with semicolon to execute query
       \q to quit

twall=> \o | cat >> file.txt
twall=> select 3;
twall=> \q
twall@ubuntu:~$ cat file.txt
 ?column?
----------
        1
(1 row)

 ?column?
----------
        2
(1 row)

 ?column?
----------
        3
(1 row)