Hi all,

Consider a table with a row function attached (in PostgreSQL), e.g.:

CREATE TABLE foo (id serial PRIMARY KEY,
        value int not null,
        v2 int not null);

CREATE FUNCTION is_even(foo) RETURNS boolean STABLE STRICT AS $$
        SELECT $1.value %2 = 0;
$$ LANGUAGE SQL;

(modulo typos and syntax errors).

Now, I can access the function value like this:

SELECT f.id, f.value, f.v2, f.is_even FROM foo f;

or like this:

my @foos = @{ Foo::Manager->get_objects };
print $_->is_even ? 'even' : 'odd' for @foos;

So far, so good. RDBO handles it nicely (with a little patch to always
qualify column names). As long as I remember to use changes_only => 1
in save, updates work fine too.

However, the problem arises after calling:

my ($a_foo) = @{ Foo::Manager->get_objects( query => [ id => 5, is_even => 0 ] 
) };
$a_foo->v2( 5 );
$a_foo->save( changes_only => 1 );

The is_even condition is a result of my condition builder (e.g. a user
may access any foo as long as its value is even). The rather weird call
to a manager method to get one item is its artefact too.

After executing the above snippet, RDBO wants to update the is_even
column and gets barfed at by PostgreSQL (there's no is_even column).

Apparently the setter for the is_even column is called within the
get_objects function, but AIUI, this shouldn't result in marking the
column modified. I appreciate any pointers and maybe a word or two about
the Right Way to handle computed columns in RDBO.

I'm using RDBO v.0.763.

Best regards,
 Grzegorz Nosek

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Rose-db-object mailing list
Rose-db-object@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/rose-db-object

Reply via email to