select z hodinovych zaznamu

[Karel Zak]

On Thu, 10 Aug 2000, Lukas Maly wrote:

> Dobry den
> 
> Mel bych otazku, jak udelat select z techo hodnot v PostgreSQL, mozna se to
> podoba i v jinych databazich???
> 
> dat typy
> 
> id    int4    not null    4
> datum    date    4
> hodina    time    8
> hodnota    float4    4
> 
> id datum        cas      hodnota
> 
> 16|08-10-2000|17:00:04|     27
> 17|08-10-2000|17:15:02|     27
> 18|08-10-2000|17:30:02|     24
> 19|08-10-2000|17:45:02|     24
> 
> Chtel bych udelt select vsech zaznamu z 17:??:??
> 
> select * from table where hodina = 17:??:??   ???

 Co je spatne na dokumentaci PG?

select * from table where select date_part('hour', cas) = 17;
select * from table where select to_char('HH14', cas) = '17';

					Karel