dbd::interbase.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

.Sp
Supported by the driver as proposed by \s-1DBI\s0.
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 \fIprepare()\fR for binding the placeholders.
Instead of calling this method repeatedly with bind values, it would be
better to call \fIprepare()\fR once, and \fIexecute()\fR many times.
.Sp
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.
.IP "\fBcommit\fR" 4
.IX Item "commit"
.Vb 1
\&  $rc  = $dbh\->commit;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0. See also the 
notes about \fBTransactions\fR elsewhere in this document.
.IP "\fBrollback\fR" 4
.IX Item "rollback"
.Vb 1
\&  $rc  = $dbh\->rollback;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0. See also the 
notes about \fBTransactions\fR elsewhere in this document.
.IP "\fBdisconnect\fR" 4
.IX Item "disconnect"
.Vb 1
\&  $rc  = $dbh\->disconnect;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBping\fR" 4
.IX Item "ping"
.Vb 1
\&  $rc = $dbh\->ping;
.Ve
.Sp
This driver supports the ping-method, which can be used to check the 
validity of a database-handle. This is especially required by
\&\f(CW\*(C`Apache::DBI\*(C'\fR.
.IP "\fBtable_info\fR" 4
.IX Item "table_info"
.Vb 1
\&  $sth = $dbh\->table_info;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBtables\fR" 4
.IX Item "tables"
.Vb 1
\&  @names = $dbh\->tables;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBtype_info_all\fR" 4
.IX Item "type_info_all"
.Vb 1
\&  $type_info_all = $dbh\->type_info_all;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.Sp
For further details concerning the InterBase specific data-types 
please read the \*(L"InterBase Data Definition Guide\*(R".
.IP "\fBtype_info\fR" 4
.IX Item "type_info"
.Vb 1
\&  @type_info = $dbh\->type_info($data_type);
.Ve
.Sp
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fBquote\fR" 4
.IX Item "quote"
.Vb 1
\&  $sql = $dbh\->quote($value, $data_type);
.Ve
.Sp
Implemented by \s-1DBI\s0, no driver-specific impact.
.Sh "Database Handle Attributes"
.IX Subsection "Database Handle Attributes"
.IP "\fBAutoCommit\fR  (boolean)" 4
.IX Item "AutoCommit  (boolean)"
Supported by the driver as proposed by \s-1DBI\s0. According to the 
classification of \s-1DBI\s0, 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 \s-1DBI\s0'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 \fBTransactions\fR elsewhere in this document.
.IP "\fBDriver\fR  (handle)" 4
.IX Item "Driver  (handle)"
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fBName\fR  (string, read-only)" 4
.IX Item "Name  (string, read-only)"
Not yet implemented.
.IP "\fBRowCacheSize\fR  (integer)" 4
.IX Item "RowCacheSize  (integer)"
Implemented by \s-1DBI\s0, not used by the driver.
.IP "\fBib_softcommit\fR  (driver-specific, boolean)" 4
.IX Item "ib_softcommit  (driver-specific, boolean)"
Set this attribute to \s-1TRUE\s0 to use InterBase's soft commit feature (default
to \s-1FALSE\s0). Soft commit retains the internal transaction handle when
committing a transaction, while the default commit behavior always closes
and invalidates the transaction handle.
.Sp
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.
.Sp
Switching the attribute's value from \s-1TRUE\s0 to \s-1FALSE\s0 will force hard commit thus 
closing the current transaction.
.SH "STATEMENT HANDLE OBJECTS"
.IX Header "STATEMENT HANDLE OBJECTS"
.Sh "Statement Handle Methods"
.IX Subsection "Statement Handle Methods"
.IP "\fBbind_param\fR" 4
.IX Item "bind_param"
Supported by the driver as proposed by \s-1DBI\s0. 
The \s-1SQL\s0 data type passed as the third argument is ignored.
.IP "\fBbind_param_inout\fR" 4
.IX Item "bind_param_inout"
Not supported by this driver.
.IP "\fBexecute\fR" 4
.IX Item "execute"
.Vb 1
\&  $rv = $sth\->execute(@bind_values);
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBfetchrow_arrayref\fR" 4
.IX Item "fetchrow_arrayref"
.Vb 1
\&  $ary_ref = $sth\->fetchrow_arrayref;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBfetchrow_array\fR" 4
.IX Item "fetchrow_array"
.Vb 1
\&  @ary = $sth\->fetchrow_array;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBfetchrow_hashref\fR" 4
.IX Item "fetchrow_hashref"
.Vb 1
\&  $hash_ref = $sth\->fetchrow_hashref;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBfetchall_arrayref\fR" 4
.IX Item "fetchall_arrayref"
.Vb 1
\&  $tbl_ary_ref = $sth\->fetchall_arrayref;
.Ve
.Sp
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fBfinish\fR" 4
.IX Item "finish"
.Vb 1
\&  $rc = $sth\->finish;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBrows\fR" 4
.IX Item "rows"
.Vb 1
\&  $rv = $sth\->rows;
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0. 
It returns the number of \fBfetched\fR rows for select statements, otherwise
it returns \-1 (unknown number of affected rows).
.IP "\fBbind_col\fR" 4
.IX Item "bind_col"
.Vb 1
\&  $rc = $sth\->bind_col($column_number, \e$var_to_bind, \e%attr);
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBbind_columns\fR" 4
.IX Item "bind_columns"
.Vb 1
\&  $rc = $sth\->bind_columns(\e%attr, @list_of_refs_to_vars_to_bind);
.Ve
.Sp
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBdump_results\fR" 4
.IX Item "dump_results"
.Vb 1
\&  $rows = $sth\->dump_results($maxlen, $lsep, $fsep, $fh);
.Ve
.Sp
Implemented by \s-1DBI\s0, no driver-specific impact.
.Sh "Statement Handle Attributes"
.IX Subsection "Statement Handle Attributes"
.IP "\fB\s-1NUM_OF_FIELDS\s0\fR  (integer, read-only)" 4
.IX Item "NUM_OF_FIELDS  (integer, read-only)"
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fB\s-1NUM_OF_PARAMS\s0\fR  (integer, read-only)" 4
.IX Item "NUM_OF_PARAMS  (integer, read-only)"
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fB\s-1NAME\s0\fR  (array-ref, read-only)" 4
.IX Item "NAME  (array-ref, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBNAME_lc\fR  (array-ref, read-only)" 4
.IX Item "NAME_lc  (array-ref, read-only)"
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fBNAME_uc\fR  (array-ref, read-only)" 4
.IX Item "NAME_uc  (array-ref, read-only)"
Implemented by \s-1DBI\s0, no driver-specific impact.
.IP "\fB\s-1TYPE\s0\fR  (array-ref, read-only)" 4
.IX Item "TYPE  (array-ref, read-only)"
Supported by the driver as proposed by \s-1DBI\s0, with 
the restriction, that the types are InterBase
specific data-types which do not correspond to 
international standards.
.IP "\fB\s-1PRECISION\s0\fR  (array-ref, read-only)" 4
.IX Item "PRECISION  (array-ref, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fB\s-1SCALE\s0\fR  (array-ref, read-only)" 4
.IX Item "SCALE  (array-ref, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fB\s-1NULLABLE\s0\fR  (array-ref, read-only)" 4
.IX Item "NULLABLE  (array-ref, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBCursorName\fR  (string, read-only)" 4
.IX Item "CursorName  (string, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBStatement\fR  (string, read-only)" 4
.IX Item "Statement  (string, read-only)"
Supported by the driver as proposed by \s-1DBI\s0.
.IP "\fBRowCache\fR  (integer, read-only)" 4
.IX Item "RowCache  (integer, read-only)"
Not supported by the driver.
.SH "TRANSACTION SUPPORT"
.IX Header "TRANSACTION SUPPORT"
The transaction behavior is controlled with the attribute AutoCommit. 
For a complete definition of AutoCommit please refer to the \s-1DBI\s0 documentation.
.PP
According to the \s-1DBI\s0 specification the default for AutoCommit is \s-1TRUE\s0. 
In this mode, any change to the database becomes valid immediately. Any 
\&\fIcommit()\fR or \fIrollback()\fR will be rejected.
.PP
If AutoCommit is switched-off, immediately a transaction will be started.
A \fIrollback()\fR will rollback and close the active transaction, then implicitly 
start a new transaction. A disconnect will issue a rollback.
.PP
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,
\&\f(CW\*(C`ib_set_tx_param()\*(C'\fR database handle method is available.
.PP
Upon a successful \f(CW\*(C`connect()\*(C'\fR, these default parameter values will be used
for every \s-1SQL\s0 operation:
.PP
.Vb 3
\&    Access mode:        read_write
\&    Isolation level:    snapshot
\&    Lock resolution:    wait
.Ve
.PP
Any of the above value can be changed using \f(CW\*(C`ib_set_tx_param()\*(C'\fR.
.IP "\fBib_set_tx_param\fR" 4
.IX Item "ib_set_tx_param"
.Vb 6
\& $dbh\->func( 
\&    \-access_mode     => \*(Aqread_write\*(Aq,
\&    \-isolation_level => \*(Aqread_committed\*(Aq,
\&    \-lock_resolution => \*(Aqwait\*(Aq,
\&    \*(Aqib_set_tx_param\*(Aq
\& );
.Ve
.Sp
Valid value for \f(CW\*(C`\-access_mode\*(C'\fR is \f(CW\*(C`read_write\*(C'\fR, or \f(CW\*(C`read_only\*(C'\fR.
.Sp
Valid value for \f(CW\*(C`\-lock_resolution\*(C'\fR is \f(CW\*(C`wait\*(C'\fR, or \f(CW\*(C`no_wait\*(C'\fR. 
In Firebird 2.0, a timeout value for wait is introduced. This can be 
specified using hash ref as lock_resolution value:
.Sp
.Vb 4
\& $dbh\->func(
\&    \-lock_resolution => { wait => 5 }, # wait for 5 seconds
\&    \*(Aqib_set_tx_param\*(Aq
\& );
.Ve
.Sp
\&\f(CW\*(C`\-isolation_level\*(C'\fR may be: \f(CW\*(C`read_committed\*(C'\fR, \f(CW\*(C`snapshot\*(C'\fR,
\&\f(CW\*(C`snapshot_table_stability\*(C'\fR.
.Sp
If \f(CW\*(C`read_committed\*(C'\fR is to be used with \f(CW\*(C`record_version\*(C'\fR or
\&\f(CW\*(C`no_record_version\*(C'\fR, then they should be inside an anonymous array:
.Sp
.Vb 4
\& $dbh\->func( 
\&    \-isolation_level => [\*(Aqread_committed\*(Aq, \*(Aqrecord_version\*(Aq],
\&    \*(Aqib_set_tx_param\*(Aq
\& );
.Ve
.Sp
Table reservation is supported since \f(CW\*(C`DBD::InterBase 0.30\*(C'\fR. 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 \f(CW\*(C`\-reserving\*(C'\fR.
.Sp
The following example reserves \f(CW\*(C`foo_table\*(C'\fR with \f(CW\*(C`read\*(C'\fR lock and \f(CW\*(C`bar_table\*(C'\fR 
with \f(CW\*(C`read\*(C'\fR lock and \f(CW\*(C`protected\*(C'\fR access:
.Sp
.Vb 10
\& $dbh\->func(
\&    \-access_mode     => \*(Aqread_write\*(Aq,
\&    \-isolation_level => \*(Aqread_committed\*(Aq,
\&    \-lock_resolution => \*(Aqwait\*(Aq,
\&    \-reserving       =>
\&        {
\&            foo_table => {
\&                lock    => \*(Aqread\*(Aq,
\&            },
\&            bar_table => {
\&                lock    => \*(Aqread\*(Aq,
\&                access  => \*(Aqprotected\*(Aq,
\&            },
\&        },
\&    \*(Aqib_set_tx_param\*(Aq
\& );
.Ve
.Sp
Possible table reservation parameters are:
.RS 4
.ie n .IP """access"" (optional)" 4
.el .IP "\f(CWaccess\fR (optional)" 4
.IX Item "access (optional)"
Valid values are \f(CW\*(C`shared\*(C'\fR or \f(CW\*(C`protected\*(C'\fR.
.ie n .IP """lock"" (required)" 4
.el .IP "\f(CWlock\fR (required)" 4
.IX Item "lock (required)"
Valid values are \f(CW\*(C`read\*(C'\fR or \f(CW\*(C`write\*(C'\fR.
.RE
.RS 4
.Sp
Under \f(CW\*(C`AutoCommit\*(C'\fR mode, invoking this method doesn't only change the
transaction parameters (as with \f(CW\*(C`AutoCommit\*(C'\fR off), but also commits the
current transaction. The new transaction parameters will be used in
any newly started transaction.
.Sp
\&\f(CW\*(C`ib_set_tx_param()\*(C'\fR can also be invoked with no parameter in which it resets
transaction parameters to the default value.
.RE
.SH "DATE, TIME, and TIMESTAMP FORMATTING SUPPORT"
.IX Header "DATE, TIME, and TIMESTAMP FORMATTING SUPPORT"
\&\f(CW\*(C`DBD::InterBase\*(C'\fR supports various formats for query results of \s-1DATE\s0, \s-1TIME\s0,
and \s-1TIMESTAMP\s0 types.
.PP
By default, it uses \*(L"%c\*(R" for \s-1TIMESTAMP\s0, \*(L"%x\*(R" for \s-1DATE\s0, and \*(L"%X\*(R" for \s-1TIME\s0,
and pass them to \s-1ANSI\s0 C's \fIstrftime()\fR 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:
.IP "\(bu" 4
At \f(CW$dbh\fR level
.Sp
This replaces the default values. Example:
.Sp
.Vb 3
\& $dbh\->{ib_timestampformat} = \*(Aq%m\-%d\-%Y %H:%M\*(Aq;
\& $dbh\->{ib_dateformat} = \*(Aq%m\-%d\-%Y\*(Aq;
\& $dbh\->{ib_timeformat} = \*(Aq%H:%M\*(Aq;
.Ve
.IP "\(bu" 4
At \f(CW$sth\fR level
.Sp
This overrides the default values only for the currently prepared statement. Example:
.Sp
.Vb 7
\& $attr = {
\&    ib_timestampformat => \*(Aq%m\-%d\-%Y %H:%M\*(Aq,
\&    ib_dateformat => \*(Aq%m\-%d\-%Y\*(Aq,
\&    ib_timeformat => \*(Aq%H:%M\*(Aq,
\& };
\& # then, pass it to prepare() method. 
\& $sth = $dbh\->prepare($sql, $attr);
.Ve
.PP
Since locale settings affect the result of \fIstrftime()\fR, if your application
is designed to be portable across different locales, you may consider using these
two special formats: '\s-1TM\s0' and '\s-1ISO\s0'. \f(CW\*(C`TM\*(C'\fR returns a 9\-element list, much like
Perl's \fIlocaltime()\fR. The \f(CW\*(C`ISO\*(C'\fR format applies \fIsprintf()\fR's pattern
\&\*(L"%04d\-%02d\-%02d \f(CW%02d:\fR%02d:%02d.%04d\*(R" for \s-1TIMESTAMP\s0, \*(L"%04d\-%02d\-%02d\*(R" for
\&\s-1DATE\s0, and \*(L"%02d:%02d:%02d.%04d\*(R" for \s-1TIME\s0.
.PP
\&\f(CW\*(C`$dbh\->{ib_time_all}\*(C'\fR can be used to specify all of the three formats at
once. Example:
.PP
.Vb 1
\& $dbh\->{ib_time_all} = \*(AqTM\*(Aq;
.Ve
.SH "EVENT ALERT SUPPORT"
.IX Header "EVENT ALERT SUPPORT"
Event alerter is used to notify client applications whenever something is
happened on the database. For this to work, a trigger should be created,
which then calls \s-1POST_EVENT\s0 to post the event notification to the interested
client. A client could behave in two ways: wait for the event synchronously,
or register a callback which will be invoked asynchronously each time a
posted event received.
.ie n .IP """ib_init_event""" 4
.el .IP "\f(CWib_init_event\fR" 4
.IX Item "ib_init_event"