constraint definition on an array column?

On Fri, Sep 11, 2009 at 10:34 AM, Gauthier, Dave
<dave.gauthier@intel.com> wrote:

Hi:

Is it possible to define a constraint that checks all elements of an array
type column?

Example...

create table foo (asset text, owner_uids text[]);

I also have a  plperlu function that checks to see if a given uid is valid
(returns a 0/1).  It’s called validate_uid(text),  This function could be
modified to handle a list of uids if that was needed.

I want something like...

constraint validate_all_owner_uids check (select validate_uid(owner_uid) =
1)

...but owner_uid is an array, not any one distinct value.

1)     Is there a way to pass in a list for the plperlu to evaluate (return
0 if any uid is invalid)?

2)     Is there some sort of syntactical support for defining constraints on
array columns?

there doesn't have to be. since a constraint can invoke a function
(preferably immutable), you can do anything you want regarding
validating the array.

merlin