$dbh->do('exec sp_MyStoredProg @foo=' . $dbh->quote($bar));

##</code><code>##

$bar=~s/'/''/g;
$dbh->do("exec sp_MyStoredProg \@foo='$bar'");

##</code><code>##

my $sth=$dbh->prepare('exec sp_MyStoredProg @foo=?');
$sth->execute($bar);

##</code><code>##

DBD::ODBC::st execute failed: [Microsoft][ODBC SQL Server Driver][SQL Server]Line 1: Incorrect syntax near 's'. (SQL-37000)
[Microsoft][ODBC SQL Server Driver][SQL Server]Unclosed quotation mark before the character string '.... (SQL-37000)(DBD: st_execute/SQLExecute err=-1) at testdiff.pl line 113.