psql's describe command (for sequences) output improvement

On 04/12/2007, Aftab Hussain <aftab.hussain@enterprisedb.com> wrote:

Hi all,

I have a patch which tries to improve the '\d some_sequence_name' command
output in psql utility. Before sending the patch to pgsql-patches I just
want to know your opinion whether the new output of the command is OK or it
needs to be modified before sending it to pgsql-patches.

For comparison purpose, here is the output of the '\d some_sequence_name'
command:

-- Say we have created a sequence named 'test_seq' already as CREATE
SEQUENCE test_seq.

--
-- Output: before applying the patch.
--
testdb=# \d test_seq;
Sequence "public.test_seq"
Column | Type
---------------+---------
sequence_name | name
last_value | bigint
increment_by | bigint
max_value | bigint
min_value | bigint
cache_value | bigint
log_cnt | bigint
is_cycled | boolean
is_called | boolean

--
-- Output: after applying the patch.
--
testdb=# \d test_seq;
Sequence "public.test_seq"
last_value | increment_by | max_value | min_value | cache_value
| log_cnt | is_cycled | is_called

------------+--------------+---------------------+-----------+-------------+---------+-----------+-----------
1 | 1 | 9223372036854775807 | 1 | 1
| 1 | f | f

Thanks in advance for your feedback(s).

--
Aftab.

Why?

is that not what

select * from test_seq;

does already.

\d command return meta data not data.

Peter Childs

On Dec 4, 2007 7:47 PM, Peter Childs <peterachilds@gmail.com> wrote:

On 04/12/2007, Aftab Hussain <aftab.hussain@enterprisedb.com> wrote:

Hi all,

I have a patch which tries to improve the '\d some_sequence_name'
command output in psql utility. Before sending the patch to pgsql-patches I
just want to know your opinion whether the new output of the command is OK
or it needs to be modified before sending it to pgsql-patches.

For comparison purpose, here is the output of the '\d
some_sequence_name' command:

-- Say we have created a sequence named 'test_seq' already as CREATE
SEQUENCE test_seq.

--
-- Output: before applying the patch.
--
testdb=# \d test_seq;
Sequence "public.test_seq"
Column | Type
---------------+---------
sequence_name | name
last_value | bigint
increment_by | bigint
max_value | bigint
min_value | bigint
cache_value | bigint
log_cnt | bigint
is_cycled | boolean
is_called | boolean

--
-- Output: after applying the patch.
--
testdb=# \d test_seq;
Sequence "public.test_seq"
last_value | increment_by | max_value | min_value |
cache_value | log_cnt | is_cycled | is_called

------------+--------------+---------------------+-----------+-------------+---------+-----------+-----------
1 | 1 | 9223372036854775807 | 1 |
1 | 1 | f | f

Thanks in advance for your feedback(s).

--
Aftab.

Why?

is that not what

select * from test_seq;

does already.

\d command return meta data not data.

Peter Childs

In general, \d command is working perfectly for database objects.

For sequences, I think the current \d some_sequence command's output is
displaying information which does not help the end user very much. Also
isn't the newly display information (same as information provided by 'select
* from test_seq;' statement) is/can-be-considered the metadata information
about the sequences queried about (since for the returning sequences data we
have nextval('...'), currval('...') functions)?

Please correct me if I am wrong or have missed something.

Aftab Hussain.
EnterpriseDB. www.enterprisedb.com

Aftab Hussain wrote:

In general, \d command is working perfectly for database objects.

For sequences, I think the current \d some_sequence command's output is
displaying information which does not help the end user very much. Also
isn't the newly display information (same as information provided by 'select
* from test_seq;' statement) is/can-be-considered the metadata information
about the sequences queried about (since for the returning sequences data we
have nextval('...'), currval('...') functions)?

Yes, you are kind of right that \d on sequences provides unhelpful
output, but having it display the sequence values seems odd. TODO has:

o Have psql show current values for a sequence

Maybe \d+ sequence_name should add a column that shows the current
values:

test=> \d+ x
Sequence "public.x"
Column | Type | Value | Description
---------------+---------+----------------------
sequence_name | name | x
last_value | bigint | 1
increment_by | bigint |
max_value | bigint |
min_value | bigint |
cache_value | bigint |
log_cnt | bigint |
is_cycled | boolean |
is_called | boolean |

--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com

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