Bug #605: timestamp(timestamp('a timestamp)) no longer works

Started by Nonamealmost 24 years ago6 messages
#1Noname
pgsql-bugs@postgresql.org

Andrew McMillan (andrew@catalyst.net.nz) reports a bug with a severity of 3
The lower the number the more severe it is.

Short Description
timestamp(timestamp('a timestamp)) no longer works

Long Description
In version 7.2 it seems that I can't reduntantly cast value to timestamp if it is already a timestamp.

I do this reasonably often in my code by way of being paranoid that I might have a date, or a time, where I for sure _really_ want it to be a timestamp...

It's cleaning up some bugs in my code, I suppose, but I kind of like making it explicit to people who might come along after me :-)

Sample Code
Here's the broken query:

pcnz=# select timestamp('2002-03-01'::timestamp);
ERROR: parser: parse error at or near "'"
pcnz=# select version();
version
-------------------------------------------------------------
PostgreSQL 7.2 on i686-pc-linux-gnu, compiled by GCC 2.95.4
(1 row)

I notice that int4(int4()) still works:

pcnz=# select int4( '777'::int4 );
int4
------
777
(1 row)

A couple of older versions where this worked:

pcnz=# select timestamp('2002-03-01'::timestamp);
timestamp
------------------------
2002-03-01 00:00:00+13
(1 row)

pcnz=# select version();
version
---------------------------------------------------------------
PostgreSQL 7.0.3 on i686-pc-linux-gnu, compiled by gcc 2.95.2
(1 row)

stimulus=# select timestamp('2002-03-01'::timestamp);
timestamp
------------------------
2002-03-01 00:00:00+13
(1 row)

stimulus=# select version();
version
---------------------------------------------------------------
PostgreSQL 7.1.3 on i686-pc-linux-gnu, compiled by GCC 2.95.4
(1 row)

No file was uploaded with this report

#2Tom Lane
tgl@sss.pgh.pa.us
In reply to: Noname (#1)
Re: Bug #605: timestamp(timestamp('a timestamp)) no longer works

pgsql-bugs@postgresql.org writes:

timestamp(timestamp('a timestamp)) no longer works

timestamp(x) is a type name now. In place of timestamp(foo) use

"timestamp"(foo)
foo::timestamp
CAST(foo AS timestamp)

And yes, this is pointed out in the migration notes...

regards, tom lane

#3Thomas Lockhart
lockhart@fourpalms.org
In reply to: Noname (#1)
Re: Bug #605: timestamp(timestamp('a timestamp)) no longer works

timestamp(timestamp('a timestamp)) no longer works
I do this reasonably often in my code by way of being paranoid
that I might have a date, or a time, where I for sure _really_
want it to be a timestamp...
pcnz=# select timestamp('2002-03-01'::timestamp);
ERROR: parser: parse error at or near "'"

You *can* coerce timestamps to be timestamps, but in 7.2 non-standard
syntax no longer works to do this. The reason is that "timestamp(p)" now
follows the SQL9x usage of defining a timestamp type with precision "p".
So trying to call a function "timestamp()" no longer works as it did.

You can use SQL9x syntax for the type coersion:

select cast('2002-03-01'::timestamp as timestamp);

or (not recommended) you can cheat and force the call to the function by
surrounding it in double-quotes:

select "timestamp"('2002-03-01'::timestamp);

hth

- Thomas

#4Thomas Lockhart
lockhart@fourpalms.org
In reply to: Noname (#1)
Re: Bug #605: timestamp(timestamp('a timestamp)) no longer works

How would I go about clearing this "bug" from the bug database? I
haven't looked at the bugtool in quite some time, but I'm not seeing a
reference to it on the web site...

- Thomas

#5Thomas Lockhart
lockhart@fourpalms.org
In reply to: Thomas Lockhart (#4)
Re: Bug #605: timestamp(timestamp('a timestamp)) no longer works

Go to: http://www.ca.postgresql.org/bugs/admin/managebugs.php and
you should be able to select and remove/update/whatever it.

Warning: Unable to connect to PostgreSQL server:
No pg_hba.conf entry for host 64.49.215.8,
user vev, database postgresql in
/usr/local/www/www/html/bugs/admin/opendb.inc on line 3
Unable to access database

#6Andrew McMillan
andrew@catalyst.net.nz
In reply to: Thomas Lockhart (#3)
Re: Bug #605: timestamp(timestamp('a timestamp)) no longer works

On Sat, 2002-03-02 at 04:16, Thomas Lockhart wrote:

timestamp(timestamp('a timestamp)) no longer works
I do this reasonably often in my code by way of being paranoid
that I might have a date, or a time, where I for sure _really_
want it to be a timestamp...
pcnz=# select timestamp('2002-03-01'::timestamp);
ERROR: parser: parse error at or near "'"

You *can* coerce timestamps to be timestamps, but in 7.2 non-standard
syntax no longer works to do this. The reason is that "timestamp(p)" now
follows the SQL9x usage of defining a timestamp type with precision "p".
So trying to call a function "timestamp()" no longer works as it did.

You can use SQL9x syntax for the type coersion:

select cast('2002-03-01'::timestamp as timestamp);

or (not recommended) you can cheat and force the call to the function by
surrounding it in double-quotes:

select "timestamp"('2002-03-01'::timestamp);

Thanks Thomas,

I wasn't aware of that SQL9x timestamp precision, which was why it
seemed like a strange change to me.

Sorry to have not read the migration issues before filing this - I
thought from following these mailing lists that I knew them already :-)

Cheers,
Andrew.
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