Re: DBD::Pg and date operations

[Ronald J Kimball]

On Wed, Jun 06, 2001 at 10:43:52AM -0400, Jeff Boes wrote:
> 
> I have a date expression in a scalar like this:
> 
> $mydate = q!timestamp 'today' - interval '30 days'!;
> 
> I want to execute a statement like this:
> 
> $stmt = $dbh->prepare('SELECT * FROM foo WHERE date_added > ?');
> $stmt->execute($mydate);

You can't.  Placeholders may only be used with simple values.
timestamp 'today' - interval '30 days' is an expression.

> DBD::Pg reports that the date is invalid. But if I change this to
> 
> $stmt = $dbh->prepare("SELECT * FROM foo WHERE date_added > $mydate");
> 
> it's fine. What am I missing here?

Try:

$stmt = $dbh->prepare(<<'EndOfSQL');
  SELECT * FROM foo
  WHERE date_added > timestamp 'today' - interval ?
EndOfSQL

$interval = '30 days';

$stmt->execute($interval);


Ronald