Question about placeholders/variables in insert statements

All

I have a question regarding Insert statements using placeholders.

Is it possible to replace the placeholders with variables? 
I have tried and it gives me the following error :
        DBD::Sybase::st execute failed: Server message number=128 
severity=15 state=1 line=1 text=The name 'U' is illegal in this context. 
Only constants, constant expressions, or        variables allowed here. 
Column names are illegal.


So for example from this:

$sth=$dbh-prepare("INSERT INTO table (column1, column2) VALUES (?,?)");
$sth->execute($value1, $value2);

to this:

$sth=$sbh->prepare("INSERT INTO table (column1, column2) VALUES ($value1, 
$value2)");
$sth->execute;

Just curious is this is possible

Thanks

Robert Gorrebeeck
EAI Developer
Concentra
5080 Spectrum Drive, Suite 1200W
Addison, TX 75001
972.725.6956
[email protected]
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