Re: Placeholder queries

Lukas Smith wrote:

From: Jeroen Houben [mailto:jeroen@terena.nl] Sent: Thursday, April 10, 2003 2:34 PM

In this month's PHP magazine I read that with PEAR::DB you can do placeholder queries like this: $file = '/tmp/image.png'; $sql = 'INSERT INTO mytable (id, myblob) VALUES (?,&)'; $id = $conn->nextId('mytable_id'); $conn->query($sql, array($id, $file)); I was familiar with prepared queries using a questionmark. What was

new

to me, and perhaps to a lot of people, is that the '&' symbol will be replaced with the contents of the file. Very cool. Does this (or something similar) also work in PEAR::MDB ?

PEAR::DB also has "!" for values what will directly be used (like integers). Well I have been banging my head on that one a bit. Unfortunately nobody ever replied to my questions on the PEAR mailinglists. Basically PEAR::DB splits things up in 3 different types: 1) Data that needs to be quoted 2) Data that can be left as is 3) LOBs This does not sufficiently abstract things however. MDB supports other datatypes as well that might need special attention (like timestamps). As such MDB has the following datatypes: 1) Text data type 2) Boolean data type 3) Integer data type 4) Decimal data type 5) Float data type 6) Date data type 7) Time data type 8) Time stamp data type 9) Binary Large object (file) data types 10) Character Large object (file) data types 6-8 can be combined into one datatype for this purposes. So we could use ? for text, ! for integers and & for blobs. What happens with the other datatypes? It's ok to have placeholders just for a selection of types isn't it? Or is that bad practice? I could see that for MDB a placeholder for LOBs would be very useful, because the LOB will then be created behind the scenes and the user does not need to worry about it.

Jeroen