hi
 the table pg_attribute have the attribute  "attlen" , and this attribute will
store the attribute length. For example , when integer , this value will be 4.
But if attribute type is Char(xx), this value will be -1. This is because it
reference the bychar in pg_type table.

So, where is the Char() length information store ??
and what time will system check this string length constraint ?

thanks for your help!
Kao , Nchu Taiwan







hi the table pg_attribute have the 
attribute  "attlen" , and this attribute willstore the attribute 
length. For example , when integer , this value will be 4.But if attribute 
type is Char(xx), this value will be -1. This is because itreference the 
bychar in pg_type table.So, where is the Char() length information store 
??and what time will system check this string length constraint 
?thanks for your help!Kao , Nchu 
Taiwan
Mon, 1 Dec 2003 18:31:56 +0800
"phd9110" <phd9110@cs.nchu.edu.tw>
Where does catalog store CHAR length ? 
On Mon, Dec 01, 2003 at 06:31:56PM +0800, phd9110 wrote:

>  the table pg_attribute have the attribute  "attlen" , and this attribute will
> store the attribute length. For example , when integer , this value will be 4.
> But if attribute type is Char(xx), this value will be -1. This is because it
> reference the bychar in pg_type table.
> 
> So, where is the Char() length information store ??

atttypmod is the maximum length + 4.

-- 
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"El destino baraja y nosotros jugamos" (A. Schopenhauer)

Mon, 1 Dec 2003 10:32:17 -0300
Alvaro Herrera <alvherre@dcc.uchile.cl>
Re: Where does catalog store CHAR length ?