NAME¶
Data::ObjectDriver::Driver::DBD - base class for database drivers
SYNOPSIS¶
package SomeObject;
use base qw( Data::ObjectDriver::BaseObject );
__PACKAGE__->install_properties({
...
driver => Data::ObjectDriver::Driver::DBI->new(
...
dbd => Data::ObjectDriver::Driver::DBD->new('mysql'),
),
});
DESCRIPTION¶
Data::ObjectDriver::Driver::DBD is the base class for
database
drivers. Database drivers handle the peculiarities of specific database
servers to provide an abstract API to the
object drivers. While
database drivers operate on queries and database concepts like the last insert
ID and binding attributes for a query, object drivers operate on objects
higher level concepts like caching and partitioning.
Database drivers are used with "Data::ObjectDriver::Driver::DBI"
object drivers. If you are making an object driver that doesn't use
"DBI", you do not need a database driver; implement your custom
behavior in your "Data::ObjectDriver" subclass directly.
USAGE¶
"Data::ObjectDriver::Driver::DBD->new($name)"¶
Creates a new database driver of the given subclass type. That is,
"new('mysql')" would create a new instance of
"Data::ObjectDriver::Driver::DBD::mysql".
"$dbd->init_dbh($dbh)"¶
Initializes the given database handle connected to this driver's type of
database.
By default, no operation is performed. Override this method if your type of
database must do further initialization that other database servers don't
need, such as setting an operative time zone.
"$dbd->bind_param_attributes($type)"¶
Returns a hashref to pass to the "DBI" statement method
"bind_param", to describe the SQL type of a column defined as $type
in an object class's "column_defs" mapping.
By default, no operation is performed. Override this method if your type of
database needs such type hinting for some fields, such as specifying a
parameter is a "BLOB".
Note that object classes must define your custom types in their
"column_defs" mappings for those classes to be compatible with your
"DBD". Make sure to document any custom types you implement.
"$dbd->db_column_name($datasource, $column)"¶
Returns a decorated column name. For example, if your database requires column
names to be prepended with table names, that concatenation would occur in this
method.
By default, "db_column_name" returns the column name unmodified.
"$dbd->fetch_id()"¶
Returns the autogenerated ID of the most recently inserted record, or
"undef" if this feature is not supported.
By default, "fetch_id" returns "undef".
"$dbd->map_error_code($code, $msg)"¶
Returns a "Data::ObjectDriver::Errors" code for the given database
error, or "undef" if no equivalent has been defined.
By default, "map_error_code" returns "undef" for every
error.
"$dbd->sql_for_unixtime()"¶
Returns the SQL for querying the current UNIX time on the database server, or a
UNIX time to use as the remote time.
By default, "sql_for_unixtime" returns the value of perl
"time()" on the local machine.
"$dbd->offset_implemented()"¶
Returns true if the database this driver represents supports "OFFSET"
clauses.
By default, "offset_implemented" returns true.
"$dbd->can_delete_with_limit()"¶
Returns true if the database this driver represents supports "LIMIT"
clauses on "DELETE" statements.
By default, "can_delete_with_limit" returns false.
"$dbd->can_prepare_cached_statements()"¶
Returns true if the database this driver can cope with preparing a cached
statement.
By default, "can_delete_with_limit" returns true.
"$dbd->is_case_insensitive()"¶
Returns true if the database this driver represents normally compares string
fields case insensitively.
By default, "is_case_insensitive" returns false.
"$dbd->can_replace()"¶
Returns true if the database this driver represents supports "REPLACE
INTO" statements.
By default, "can_replace" returns false.
"$dbd->force_no_prepared_cache()"¶
Returns false if the database this driver represents supports the
"prepare_cached" method on its DBI database handles.
By default, "force_no_prepared_cache" returns false.
"$dbd->sql_class()"¶
Provides the package name of the class responsible for representing SQL queries.
This method returns 'Data::ObjectDriver::SQL', but may be overridden to return
a package that has a similar interface but produces SQL that is compatible
with that DBD driver. The package provided must already be loaded and
available for use.
LICENSE¶
Data::ObjectDriver is free software; you may redistribute it and/or
modify it under the same terms as Perl itself.
AUTHOR & COPYRIGHT¶
Except where otherwise noted,
Data::ObjectDriver is Copyright 2005-2006
Six Apart, cpan@sixapart.com. All rights reserved.