Safety by example

use DBI;

use Text::Wrap;

$dbh = DBI->connect(…, …, …, {

AutoCommit => 0, RaiseError => 1

});

eval {

$sth = $dbh->prepare('insert into table values (?)');

foreach (@array_of_long_strings) {

$text = wrap($_);

$sth->execute($test);

}

};

$@ ? $dbh->rollback : $dbh->commit;

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Notes:

Classic example:

bank account transfer:

debit one account

credit another account

must be an ‘atomic’ operation.

Can’t allow debit without the credit.

Server-side errors: disk crash etc

Client side errors: program die()’s or is killed