I understand how to use placeholders. But how do you use the column name as a variable? Example:

my $sth = $dbh->prepare('SELECT DISTINCT email FROM contacts WHERE gue
+st = ? ORDER BY email'); 
     $sth->execute($value) or die $sth->errstr;

[download]
This works fine.

But how can you pass a variable into the first part of the WHERE clause? Example:

my $sth = $dbh->prepare('SELECT DISTINCT email FROM contacts WHERE ? =
+ ? ORDER BY email'); 
     $sth->execute($value1,$value2) or die $sth->errstr;

[download]

This doesn't work. I want to pass a variable into the statement that chooses one of the many column names I have in the DB. (MySQL).

I've tried every variation I can and searched through all the docs I have and FAQ's and can't find any reference to this. Is it possible?

peppiv

Look at me! I'm flinging!

In reply to Passing a value into a WHERE clause by peppiv

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