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=back

There's lots more to it, so please refer to the docs on the SQLite web
page, listed above, for SQL details. Also refer to L<DBI> for details
on how to use DBI itself.

=head1 CONFORMANCE WITH DBI SPECIFICATION

The API works like every DBI module does. Please see L<DBI> for more
details about core features.

Currently many statement attributes are not implemented or are
limited by the typeless nature of the SQLite database.

=head1 DRIVER PRIVATE ATTRIBUTES

=head2 Database Handle Attributes

=over 4

=item sqlite_version

Returns the version of the SQLite library which DBD::SQLite is using,
e.g., "2.8.0". Can only be read.

=item unicode

If set to a true value, DBD::SQLite will turn the UTF-8 flag on for all text
strings coming out of the database. For more details on the UTF-8 flag see
L<perlunicode>. The default is for the UTF-8 flag to be turned off.

Also note that due to some bizareness in SQLite's type system (see
http://www.sqlite.org/datatype3.html), if you want to retain
blob-style behavior for B<some> columns under C<< $dbh->{unicode} = 1
>> (say, to store images in the database), you have to state so
explicitely using the 3-argument form of L<DBI/bind_param> when doing
updates:

    use DBI qw(:sql_types);
    $dbh->{unicode} = 1;
    my $sth = $dbh->prepare
         ("INSERT INTO mytable (blobcolumn) VALUES (?)");
    $sth->bind_param(1, $binary_data, SQL_BLOB); # binary_data will
    # be stored as-is.

Defining the column type as BLOB in the DDL is B<not> sufficient.

=back

=head1 DRIVER PRIVATE METHODS

=head2 $dbh->func('last_insert_rowid')

This method returns the last inserted rowid. If you specify an INTEGER PRIMARY
KEY as the first column in your table, that is the column that is returned.
Otherwise, it is the hidden ROWID column. See the sqlite docs for details.

Note: You can now use $dbh->last_insert_id() if you have a recent version of
DBI.

=head2 $dbh->func( 'busy_timeout' )

Retrieve the current busy timeout.

=head2 $dbh->func( $ms, 'busy_timeout' )

Set the current busy timeout. The timeout is in milliseconds.

=head2 $dbh->func( $name, $argc, $func_ref, "create_function" )

This method will register a new function which will be useable in SQL
query. The method's parameters are:

=over

=item $name

The name of the function. This is the name of the function as it will
be used from SQL.

=item $argc

The number of arguments taken by the function. If this number is -1,
the function can take any number of arguments.

=item $func_ref

This should be a reference to the function's implementation.

=back

For example, here is how to define a now() function which returns the
current number of seconds since the epoch:

    $dbh->func( 'now', 0, sub { return time }, 'create_function' );

After this, it could be use from SQL as:

    INSERT INTO mytable ( now() );

=head2 $dbh->func( $name, $argc, $pkg, 'create_aggregate' )

This method will register a new aggregate function which can then used
from SQL. The method's parameters are:

=over

=item $name

The name of the aggregate function, this is the name under which the
function will be available from SQL.

=item $argc

This is an integer which tells the SQL parser how many arguments the
function takes. If that number is -1, the function can take any number
of arguments.

=item $pkg

This is the package which implements the aggregator interface.

=back

The aggregator interface consists of defining three methods:

=over