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radixhow can I write a validation statement to detect SQL injection

1) the canonical way to prevent SQL injection is, like ikegami and
jhourcle have pointed out already, to use placeholders (they are
even "native" in mysql-5).

2) you can use the the "quote" method from DBI, like:
... $dbh = DBI->connect(...); $sql = sprintf "SELECT name FROM users WHERE name=%s AND passwd=%s", $dbh->quote($bad_name), $dbh->quote($bad_pass); ...
For detection, you could just count the occurences of the \' char somewhere
in the input (or whatever quote the DB uses). That would be almost the only
danger (IIRC)

Regards

mwa

In reply to Re: Simple question on SQL Injection by mwah
in thread Simple question on SQL Injection by radix

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