interbase.pm

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=item B<RaiseError> (boolean, inherited)

Implemented by DBI, no driver-specific impact.

=item B<ChopBlanks> (boolean, inherited)

Supported by the driver as proposed by DBI. 

=item B<LongReadLen> (integer, inherited)

Supported by the driver as proposed by DBI.The default value is 80 bytes. 

=item B<LongTruncOk> (boolean, inherited)

Supported by the driver as proposed by DBI.

=item B<Taint> (boolean, inherited)

Implemented by DBI, no driver-specific impact.

=back

=head1 DATABASE HANDLE OBJECTS

=head2 Database Handle Methods

=over 4

=item B<selectrow_array>

  @row_ary = $dbh->selectrow_array($statement, \%attr, @bind_values);

Implemented by DBI, no driver-specific impact.

=item B<selectall_arrayref>

  $ary_ref = $dbh->selectall_arrayref($statement, \%attr, @bind_values);

Implemented by DBI, no driver-specific impact.

=item B<selectcol_arrayref>

  $ary_ref = $dbh->selectcol_arrayref($statement, \%attr, @bind_values);

Implemented by DBI, no driver-specific impact.

=item B<prepare>

  $sth = $dbh->prepare($statement, \%attr);

Supported by the driver as proposed by DBI.
When AutoCommit is On, this method implicitly starts a new transaction,
which will be automatically committed after the following execute() or the
last fetch(), depending on the statement type. For select statements,
commit automatically takes place after the last fetch(), or by explicitly 
calling finish() method if there are any rows remaining. For non-select
statements, execute() will implicitly commits the transaction. 

=item B<prepare_cached>

  $sth = $dbh->prepare_cached($statement, \%attr);

Implemented by DBI, no driver-specific impact. 

=item B<do>

  $rv  = $dbh->do($statement, \%attr, @bind_values);

Supported by the driver as proposed by DBI.
This should be used for non-select statements, where the driver doesn't take
the conservative prepare - execute steps, thereby speeding up the execution
time. But if this method is used with bind values, the speed advantage
diminishes as this method calls prepare() for binding the placeholders.
Instead of calling this method repeatedly with bind values, it would be
better to call prepare() once, and execute() many times.

See the notes for the execute method elsewhere in this document. Unlike the
execute method, currently this method doesn't return the number of affected
rows. 

=item B<commit>

  $rc  = $dbh->commit;

Supported by the driver as proposed by DBI. See also the 
notes about B<Transactions> elsewhere in this document. 

=item B<rollback>

  $rc  = $dbh->rollback;

Supported by the driver as proposed by DBI. See also the 
notes about B<Transactions> elsewhere in this document. 

=item B<disconnect>

  $rc  = $dbh->disconnect;

Supported by the driver as proposed by DBI. 

=item B<ping>

  $rc = $dbh->ping;

This driver supports the ping-method, which can be used to check the 
validity of a database-handle. This is especially required by
C<Apache::DBI>.

=item B<table_info>

  $sth = $dbh->table_info;

Supported by the driver as proposed by DBI. 

=item B<tables>

  @names = $dbh->tables;

Supported by the driver as proposed by DBI. 

=item B<type_info_all>

  $type_info_all = $dbh->type_info_all;

Supported by the driver as proposed by DBI. 

For further details concerning the InterBase specific data-types 
please read the L<InterBase Data Definition Guide>. 

=item B<type_info>

  @type_info = $dbh->type_info($data_type);

Implemented by DBI, no driver-specific impact. 

=item B<quote>

  $sql = $dbh->quote($value, $data_type);

Implemented by DBI, no driver-specific impact. 

=back

=head2 Database Handle Attributes

=over 4

=item B<AutoCommit>  (boolean)

Supported by the driver as proposed by DBI. According to the 
classification of DBI, InterBase is a database, in which a 
transaction must be explicitly started. Without starting a 
transaction, every change to the database becomes immediately 
permanent. The default of AutoCommit is on, which corresponds 
to the DBI's default. When setting AutoCommit to off, a transaction 
will be started and every commit or rollback 
will automatically start a new transaction. For details see the 
notes about B<Transactions> elsewhere in this document. 

=item B<Driver>  (handle)

Implemented by DBI, no driver-specific impact. 

=item B<Name>  (string, read-only)

Not yet implemented.

=item B<RowCacheSize>  (integer)

Implemented by DBI, not used by the driver.

=item B<ib_softcommit>  (driver-specific, boolean)

Set this attribute to TRUE to use InterBase's soft commit feature (default
to FALSE). Soft commit retains the internal transaction handle when
committing a transaction, while the default commit behavior always closes
and invalidates the transaction handle.

Since the transaction handle is still open, there is no need to start a new transaction 
upon every commit, so applications can gain performance improvement. Using soft commit is also 
desirable when dealing with nested statement handles under AutoCommit on. 

Switching the attribute's value from TRUE to FALSE will force hard commit thus 
closing the current transaction. 

=back

=head1 STATEMENT HANDLE OBJECTS

=head2 Statement Handle Methods

=over 4

=item B<bind_param>

Supported by the driver as proposed by DBI. 
The SQL data type passed as the third argument is ignored. 

=item B<bind_param_inout>

Not supported by this driver. 

=item B<execute>

  $rv = $sth->execute(@bind_values);

Supported by the driver as proposed by DBI. 

=item B<fetchrow_arrayref>

  $ary_ref = $sth->fetchrow_arrayref;

Supported by the driver as proposed by DBI. 

=item B<fetchrow_array>

  @ary = $sth->fetchrow_array;

Supported by the driver as proposed by DBI. 

=item B<fetchrow_hashref>

  $hash_ref = $sth->fetchrow_hashref;

Supported by the driver as proposed by DBI. 

=item B<fetchall_arrayref>

  $tbl_ary_ref = $sth->fetchall_arrayref;

Implemented by DBI, no driver-specific impact. 

=item B<finish>

  $rc = $sth->finish;

Supported by the driver as proposed by DBI. 

=item B<rows>

  $rv = $sth->rows;

Supported by the driver as proposed by DBI. 
It returns the number of B<fetched> rows for select statements, otherwise
it returns -1 (unknown number of affected rows).

=item B<bind_col>

  $rc = $sth->bind_col($column_number, \$var_to_bind, \%attr);

Supported by the driver as proposed by DBI. 

=item B<bind_columns>

  $rc = $sth->bind_columns(\%attr, @list_of_refs_to_vars_to_bind);

Supported by the driver as proposed by DBI. 

=item B<dump_results>

  $rows = $sth->dump_results($maxlen, $lsep, $fsep, $fh);

Implemented by DBI, no driver-specific impact. 

=back

=head2 Statement Handle Attributes

=over 4

=item B<NUM_OF_FIELDS>  (integer, read-only)

Implemented by DBI, no driver-specific impact. 

=item B<NUM_OF_PARAMS>  (integer, read-only)

Implemented by DBI, no driver-specific impact. 

=item B<NAME>  (array-ref, read-only)

Supported by the driver as proposed by DBI. 

=item B<NAME_lc>  (array-ref, read-only)

Implemented by DBI, no driver-specific impact. 

=item B<NAME_uc>  (array-ref, read-only)

Implemented by DBI, no driver-specific impact. 

=item B<TYPE>  (array-ref, read-only)

Supported by the driver as proposed by DBI, with 
the restriction, that the types are InterBase
specific data-types which do not correspond to 
international standards.

=item B<PRECISION>  (array-ref, read-only)

Supported by the driver as proposed by DBI. 

=item B<SCALE>  (array-ref, read-only)

Supported by the driver as proposed by DBI. 

=item B<NULLABLE>  (array-ref, read-only)

Supported by the driver as proposed by DBI. 

=item B<CursorName>  (string, read-only)

Supported by the driver as proposed by DBI. 

=item B<Statement>  (string, read-only)

Supported by the driver as proposed by DBI. 

=item B<RowCache>  (integer, read-only)

Not supported by the driver. 

=back

=head1 TRANSACTION SUPPORT

The transaction behavior is controlled with the attribute AutoCommit. 
For a complete definition of AutoCommit please refer to the DBI documentation. 

According to the DBI specification the default for AutoCommit is TRUE. 
In this mode, any change to the database becomes valid immediately. Any 
commit() or rollback() will be rejected. 

If AutoCommit is switched-off, immediately a transaction will be started.
A rollback() will rollback and close the active transaction, then implicitly 
start a new transaction. A disconnect will issue a rollback. 

InterBase provides fine control over transaction behavior, where users can
specify the access mode, the isolation level, the lock resolution, and the 
table reservation (for a specified table). For this purpose,
C<ib_set_tx_param()> database handle method is available. 

Upon a successful C<connect()>, these default parameter values will be used
for every SQL operation:

    Access mode:        read_write
    Isolation level:    snapshot
    Lock resolution:    wait

Any of the above value can be changed using C<ib_set_tx_param()>.

=over 4

=item B<ib_set_tx_param> 

 $dbh->func( 
    -access_mode     => 'read_write',
    -isolation_level => 'read_committed',
    -lock_resolution => 'wait',
    'ib_set_tx_param'
 );

Valid value for C<-access_mode> is C<read_write>, or C<read_only>. 

Valid value for C<-lock_resolution> is C<wait>, or C<no_wait>. 
In Firebird 2.0, a timeout value for wait is introduced. This can be 
specified using hash ref as lock_resolution value:

 $dbh->func(
    -lock_resolution => { wait => 5 }, # wait for 5 seconds
    'ib_set_tx_param'
 );

C<-isolation_level> may be: C<read_committed>, C<snapshot>,
C<snapshot_table_stability>. 

If C<read_committed> is to be used with C<record_version> or
C<no_record_version>, then they should be inside an anonymous array:

 $dbh->func( 
    -isolation_level => ['read_committed', 'record_version'],
    'ib_set_tx_param'
 );

Table reservation is supported since C<DBD::InterBase 0.30>. Names of the
tables to reserve as well as their reservation params/values are specified
inside a hashref, which is then passed as the value of C<-reserving>.

The following example reserves C<foo_table> with C<read> lock and C<bar_table> 
with C<read> lock and C<protected> access:

 $dbh->func(
    -access_mode     => 'read_write',
    -isolation_level => 'read_committed',
    -lock_resolution => 'wait',
    -reserving       =>
        {
            foo_table => {
                lock    => 'read',
            },
            bar_table => {
                lock    => 'read',
                access  => 'protected',
            },
        },
    'ib_set_tx_param'
 );

Possible table reservation parameters are:

=over 4

=item C<access> (optional)

Valid values are C<shared> or C<protected>.

=item C<lock> (required)

Valid values are C<read> or C<write>.

=back

Under C<AutoCommit> mode, invoking this method doesn't only change the
transaction parameters (as with C<AutoCommit> off), but also commits the
current transaction. The new transaction parameters will be used in
any newly started transaction. 

C<ib_set_tx_param()> can also be invoked with no parameter in which it resets
transaction parameters to the default value.

=back

=head1 DATE, TIME, and TIMESTAMP FORMATTING SUPPORT

C<DBD::InterBase> supports various formats for query results of DATE, TIME,
and TIMESTAMP types. 

By default, it uses "%c" for TIMESTAMP, "%x" for DATE, and "%X" for TIME,
and pass them to ANSI C's strftime() function to format your query results.
These values are respectively stored in ib_timestampformat, ib_dateformat,
and ib_timeformat attributes, and may be changed in two ways:

=over 

=item * At $dbh level

This replaces the default values. Example:

 $dbh->{ib_timestampformat} = '%m-%d-%Y %H:%M';
 $dbh->{ib_dateformat} = '%m-%d-%Y';
 $dbh->{ib_timeformat} = '%H:%M';

=item * At $sth level

This overrides the default values only for the currently prepared statement. Example:

 $attr = {
    ib_timestampformat => '%m-%d-%Y %H:%M',
    ib_dateformat => '%m-%d-%Y',
    ib_timeformat => '%H:%M',
 };
 # then, pass it to prepare() method.