Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
Padre::DB::HostConfig(User Contributed Perl DocumentatPadre::DB::HostConfig(3)

NAME
       Padre::DB::HostConfig - Padre::DB class for the host_config table

DESCRIPTION
       TO BE COMPLETED

METHODS
   base
	 # Returns 'Padre::DB'
	 my $namespace = Padre::DB::HostConfig->base;

       Normally	you will only need to work directly with a table class,	and
       only with one ORLite package.

       However,	if for some reason you need to work with multiple ORLite
       packages	at the same time without hardcoding the	root namespace all the
       time, you can determine the root	namespace from an object or table
       class with the "base" method.

   table
	 # Returns 'host_config'
	 print Padre::DB::HostConfig->table;

       While you should	not need the name of table for any simple operations,
       from time to time you may need it programatically. If you do need it,
       you can use the "table" method to get the table name.

   load
	 my $object = Padre::DB::HostConfig->load( $name );

       If your table has single	column primary key, a "load" method will be
       generated in the	class. If there	is no primary key, the method is not
       created.

       The "load" method provides a shortcut mechanism for fetching a single
       object based on the value of the	primary	key. However it	should only be
       used for	cases where your code trusts the record	to already exists.

       It returns a "Padre::DB::HostConfig" object, or throws an exception if
       the object does not exist.

   select
	 # Get all objects in list context
	 my @list = Padre::DB::HostConfig->select;

	 # Get a subset	of objects in scalar context
	 my $array_ref = Padre::DB::HostConfig->select(
	     'where name > ? order by name',
	     1000,
	 );

       The "select" method executes a typical SQL "SELECT" query on the
       host_config table.

       It takes	an optional argument of	a SQL phrase to	be added after the
       "FROM host_config" section of the query,	followed by variables to be
       bound to	the placeholders in the	SQL phrase. Any	SQL that is compatible
       with SQLite can be used in the parameter.

       Returns a list of Padre::DB::HostConfig objects when called in list
       context,	or a reference to an "ARRAY" of	Padre::DB::HostConfig objects
       when called in scalar context.

       Throws an exception on error, typically directly	from the DBI layer.

   iterate
	 Padre::DB::HostConfig->iterate( sub {
	     print $_->name . "\n";
	 } );

       The "iterate" method enables the	processing of large tables one record
       at a time without loading having	to them	all into memory	in advance.

       This plays well to the strength of SQLite, allowing it to do the	work
       of loading arbitrarily large stream of records from disk	while
       retaining the full power	of Perl	when processing	the records.

       The last	argument to "iterate" must be a	subroutine reference that will
       be called for each element in the list, with the	object provided	in the
       topic variable $_.

       This makes the "iterate"	code fragment above functionally equivalent to
       the following, except with an O(1) memory cost instead of O(n).

	 foreach ( Padre::DB::HostConfig->select ) {
	     print $_->name . "\n";
	 }

       You can filter the list via SQL in the same way you can with "select".

	 Padre::DB::HostConfig->iterate(
	     'order by ?', 'name',
	     sub {
		 print $_->name	. "\n";
	     }
	 );

       You can also use	it in raw form from the	root namespace for better
       control.	 Using this form also allows for the use of arbitrarily
       complex queries,	including joins. Instead of being objects, rows	are
       provided	as "ARRAY" references when used	in this	form.

	 Padre::DB->iterate(
	     'select name from host_config order by name',
	     sub {
		 print $_->[0] . "\n";
	     }
	 );

   count
	 # How many objects are	in the table
	 my $rows = Padre::DB::HostConfig->count;

	 # How many objects
	 my $small = Padre::DB::HostConfig->count(
	     'where name > ?',
	     1000,
	 );

       The "count" method executes a "SELECT COUNT(*)" query on	the
       host_config table.

       It takes	an optional argument of	a SQL phrase to	be added after the
       "FROM host_config" section of the query,	followed by variables to be
       bound to	the placeholders in the	SQL phrase. Any	SQL that is compatible
       with SQLite can be used in the parameter.

       Returns the number of objects that match	the condition.

       Throws an exception on error, typically directly	from the DBI layer.

   new
	 TO BE COMPLETED

       The "new" constructor is	used to	create a new abstract object that is
       not (yet) written to the	database.

       Returns a new Padre::DB::HostConfig object.

   create
	 my $object = Padre::DB::HostConfig->create(

	     name => 'value',

	     value => 'value',

	 );

       The "create" constructor	is a one-step combination of "new" and
       "insert"	that takes the column parameters, creates a new
       Padre::DB::HostConfig object, inserts the appropriate row into the
       host_config table, and then returns the object.

       If the primary key column "name"	is not provided	to the constructor (or
       it is false) the	object returned	will have "name" set to	the new	unique
       identifier.

       Returns a new host_config object, or throws an exception	on error,
       typically from the DBI layer.

   insert
	 $object->insert;

       The "insert" method commits a new object	(created with the "new"
       method) into the	database.

       If a the	primary	key column "name" is not provided to the constructor
       (or it is false)	the object returned will have "name" set to the	new
       unique identifier.

       Returns the object itself as a convenience, or throws an	exception on
       error, typically	from the DBI layer.

   delete
	 # Delete a single instantiated	object
	 $object->delete;

	 # Delete multiple rows	from the host_config table
	 Padre::DB::HostConfig->delete('where name > ?', 1000);

       The "delete" method can be used in a class form and an instance form.

       When used on an existing	Padre::DB::HostConfig instance,	the "delete"
       method removes that specific instance from the "host_config", leaving
       the object intact for you to deal with post-delete actions as you wish.

       When used as a class method, it takes a compulsory argument of a	SQL
       phrase to be added after	the "DELETE FROM host_config" section of the
       query, followed by variables to be bound	to the placeholders in the SQL
       phrase. Any SQL that is compatible with SQLite can be used in the
       parameter.

       Returns true on success or throws an exception on error,	or if you
       attempt to call delete without a	SQL condition phrase.

   truncate
	 # Delete all records in the host_config table
	 Padre::DB::HostConfig->truncate;

       To prevent the common and extremely dangerous error case	where deletion
       is called accidentally without providing	a condition, the use of	the
       "delete"	method without a specific condition is forbidden.

       Instead,	the distinct method "truncate" is provided to delete all
       records in a table with specific	intent.

       Returns true, or	throws an exception on error.

ACCESSORS
   name
	 if ( $object->name ) {
	     print "Object has been inserted\n";
	 } else	{
	     print "Object has not been	inserted\n";
	 }

       Returns true, or	throws an exception on error.

       REMAINING ACCESSORS TO BE COMPLETED

SQL
       The host_config table was originally created with the following SQL
       command.

	 CREATE	TABLE host_config (
	     name varchar(255) not null	primary	key,
	     value varchar(255)	not null
	 )

SUPPORT
       Padre::DB::HostConfig is	part of	the Padre::DB API.

       See the documentation for Padre::DB for more information.

AUTHOR
       Adam Kennedy <adamk@cpan.org>

COPYRIGHT
       Copyright 2008-2013 The Padre development team as listed	in Padre.pm.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       The full	text of	the license can	be found in the	LICENSE	file included
       with this module.

perl v5.24.1			  2013-11-09	      Padre::DB::HostConfig(3)

NAME | DESCRIPTION | METHODS | ACCESSORS | SQL | SUPPORT | AUTHOR | COPYRIGHT

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=Padre::DB::HostConfig&sektion=3&manpath=FreeBSD+12.0-RELEASE+and+Ports>

home | help