bichonfrise74:

Actually, placeholders *do* handle the null parameter. Constructing the update statement can do the rest...

my @fields = qw(name phone city country);
my $SQL = "update table set "
.         join(", ", map { "$_=?" } @fields)
.         "where ....";
my $ST=$DB->prepare($SQL);
while (...) {
    my @values = (.....);
    $ST->execute(@values);
}
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...roboticus

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