Обсуждение: a question about dates and timestamp

hi all

i have a table like this

id_message      int4 not null default nextval (  ...
id_abonne        int4 
texte_message  varchar() not null        
date_message   numeric not null  

the default size of numeric is 30.6

another table :

id_message  int4
id_abonne    int4
text_message text
date_message int4


in both case date_message is used to store a unix timestamp ( number of seconds
since 1st of 1970)

for example : 965340000  = 2000-08-03 00:00:00+02

my question is how can i convert the numeric or the int4 value to a date value?

which function should i use to make something like this work ?

select convert_to_date( date_message) from my_table;

2000-08-03 00:00:00+02
2000-08-01 13:56:00+02
etc etc


thanks in advance

Pozzo Ange

> my question is how can i convert the numeric or the int4 value to 
> a date value?


test=# select abstime(965293003);       abstime
------------------------2000-08-03 10:56:43+02
(1 row)
                Karel

Le jeu, 03 ao� 2000, Karel Zak a �crit :
> > my question is how can i convert the numeric or the int4 value to 
> > a date value?
> 
> 
> test=# select abstime(965293003);
>         abstime
> ------------------------
>  2000-08-03 10:56:43+02
> (1 row)
> 
>                     Karel


this is the result of the query for me :

test=> select abstime(965293003);?column?
---------
965293003
(1 row)

i must do :
select datetime(abstime( value )); if value is a int4 work ok

but for a numeric, it don't work

i have tried to convert a numeric to int4

with floor, int4, numeric_int4 nothing work !

select datetime(abstime( floor (value) ));
select datetime(abstime( int4 (value) ));
select datetime(abstime( numeric_int4 (value) ));

in all case :
ERROR:  pg_atoi: error in "952969611.000000": can't parse ".000000" 

what is the way to convert numeric to int4 ?

i know this is'nt a good choise to store timestamp in a int4 or numeric value,
but i found the database like this and know i can't change this :(

thanks

POZZO ange 

On Thu, 3 Aug 2000, Ange Michel POZZO wrote:

> Le jeu, 03 aoű 2000, Karel Zak a écrit :
> > > my question is how can i convert the numeric or the int4 value to 
> > > a date value?
> > 
> > 
> > test=# select abstime(965293003);
> >         abstime
> > ------------------------
> >  2000-08-03 10:56:43+02
> > (1 row)
> > 
> >                     Karel
> 
> 
> this is the result of the query for me :
> 
> test=> select abstime(965293003);
>  ?column?
> ---------
> 965293003
> (1 row)

Ooops I use CVS version, but you have probably 6.5...

Sorry, Now I haven't time check what is 7.1 / 7.0 / 6.5 feature.

in current code:

test=# select '965293003.000001'::int;
ERROR:  pg_atoi: error in "965293003.000001": can't parse ".000001"
test=# select '965293003.000001'::numeric(9, 0);?column?
-----------965293003
(1 row)

test=# select '965293003.000001'::numeric(9, 0)::int;?column?
-----------965293003
(1 row)

test=# select abstime('965293003.000001'::numeric(9, 0)::int);       abstime
------------------------2000-08-03 10:56:43+02
(1 row)


BTW. The postgreSQL has good date/time support; why you use slow and    expensive numeric?

Ange Michel POZZO <poange@technologist.com> writes:
> select datetime(abstime( floor (value) ));
> select datetime(abstime( int4 (value) ));
> select datetime(abstime( numeric_int4 (value) ));

> in all case :
> ERROR:  pg_atoi: error in "952969611.000000": can't parse ".000000" 

That was fixed in January.  Update to 7.0 and it'll work fine.
You might be able to make it work in 6.5 like this:abstime(int4(float8(numeric)))
        regards, tom lane