Programming the Perl DBI

Notation and Conventions

The following conventions are used in this document:

$dbh

Database handle object

$sth

Statement handle object

$drh

Driver handle object (rarely seen or used in applications)

$h

Any of the handle types above ($dbh, $sth, or $drh)

$rc

General return code (boolean: true=ok, false=error)

$rv

General Return Value (typically an integer)

@ary

List of values returned from the database, typically a row of data

$rows

Number of rows processed (if available, else -1)

$fh

A filehandle

undef

NULL values are represented by undefined values in Perl

\%attr

Reference to a hash of attribute values passed to methods

Note that Perl will automatically destroy database and statement handle objects if all references to them are deleted.