"M. Addlework" <[EMAIL PROTECTED]> writes:
> > > Kristian Nielsen [EMAIL PROTECTED] wrote:
> > >> Could you briefly explain what an INSERT/UPDATE cursor is?
> UPDATE <table> set <column> = <value> where CURRENT OF X;
> The original poster was correct that you can't do this directly in
> DBI. However, below is a technique which is functionally identical:
>
> $sth = $dbi->prepare("select ROWID, x.* from <table> x FOR UPDATE");
> $stu = $dbh->prepare("update <table> set <column> = <value> where ROWID = ?");
>
> $sth->execute;
> while ($r = $sth->fetchrow_hashref) {
> $stu->execute($r->{ROWID});
> }
>
> This is essentially what's happening with the WHERE CURRENT OF clause.
Ah, I see. And with this technique (and a DBI driver with native
execute_array() support), you could even collect all the ROWIDs in an
array and do all the updates/deletes in a single execute_array() at the
end of the loop, avoiding having a database roundtrip for every
row. That ought to me much more effective for large row sizes,
especially if the client is running on a different machine than the
database server.
Thanks!
- Kristian.
