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DBIx::Class::Row(3)                  User Contributed Perl Documentation                 DBIx::Class::Row(3)



NAME
       DBIx::Class::Row - Basic row methods

SYNOPSIS
DESCRIPTION
       This class is responsible for defining and doing basic operations on rows derived from
       DBIx::Class::ResultSource objects.

       Row objects are returned from DBIx::Class::ResultSets using the create, find, next and all methods,
       as well as invocations of 'single' ( belongs_to, has_one or might_have) relationship accessors of
       DBIx::Class::Row objects.

METHODS
   new
         my $row = My::Class->new(\%attrs);

         my $row = $schema->resultset('MySource')->new(\%colsandvalues);

       Arguments: \%attrs or \%colsandvalues
       Returns: A Row object

       While you can create a new row object by calling "new" directly on this class, you are better off
       calling it on a DBIx::Class::ResultSet object.

       When calling it directly, you will not get a complete, usable row object until you pass or set the
       "result_source" attribute, to a DBIx::Class::ResultSource instance that is attached to a
       DBIx::Class::Schema with a valid connection.

       $attrs is a hashref of column name, value data. It can also contain some other attributes such as the
       "result_source".

       Passing an object, or an arrayref of objects as a value will call "set_from_related" in
       DBIx::Class::Relationship::Base for you. When passed a hashref or an arrayref of hashrefs as the
       value, these will be turned into objects via new_related, and treated as if you had passed objects.

       For a more involved explanation, see "create" in DBIx::Class::ResultSet.

       Please note that if a value is not passed to new, no value will be sent in the SQL INSERT call, and
       the column will therefore assume whatever default value was specified in your database. While DBIC
       will retrieve the value of autoincrement columns, it will never make an explicit database trip to
       retrieve default values assigned by the RDBMS. You can explicitly request that all values be fetched
       back from the database by calling "discard_changes", or you can supply an explicit "undef" to columns
       with NULL as the default, and save yourself a SELECT.

        CAVEAT:

        The behavior described above will backfire if you use a foreign key column
        with a database-defined default. If you call the relationship accessor on
        an object that doesn't have a set value for the FK column, DBIC will throw
        an exception, as it has no way of knowing the PK of the related object (if
        there is one).

   insert
         $row->insert;

       Arguments: none
       Returns: The Row object

       Inserts an object previously created by "new" into the database if it isn't already in there. Returns
       the object itself. To insert an entirely new row into the database, use "create" in
       DBIx::Class::ResultSet.

       To fetch an uninserted row object, call new on a resultset.

       This will also insert any uninserted, related objects held inside this one, see "create" in
       DBIx::Class::ResultSet for more details.

   in_storage
         $row->in_storage; # Get value
         $row->in_storage(1); # Set value

       Arguments: none or 1|0
       Returns: 1|0

       Indicates whether the object exists as a row in the database or not. This is set to true when "find"
       in DBIx::Class::ResultSet, "create" in DBIx::Class::ResultSet or "insert" in DBIx::Class::ResultSet
       are used.

       Creating a row object using "new" in DBIx::Class::ResultSet, or calling "delete" on one, sets it to
       false.

   update
         $row->update(\%columns?)

       Arguments: none or a hashref
       Returns: The Row object

       Throws an exception if the row object is not yet in the database, according to "in_storage".

       This method issues an SQL UPDATE query to commit any changes to the object to the database if
       required (see "get_dirty_columns").  It throws an exception if a proper WHERE clause uniquely
       identifying the database row can not be constructed (see significance of primary keys for more
       details).

       Also takes an optional hashref of "column_name => value" pairs to update on the object first. Be
       aware that the hashref will be passed to "set_inflated_columns", which might edit it in place, so
       don't rely on it being the same after a call to "update".  If you need to preserve the hashref, it is
       sufficient to pass a shallow copy to "update", e.g. ( { %{ $href } } )

       If the values passed or any of the column values set on the object contain scalar references, e.g.:

         $row->last_modified(\'NOW()');
         # OR
         $row->update({ last_modified => \'NOW()' });

       The update will pass the values verbatim into SQL. (See SQL::Abstract docs).  The values in your Row
       object will NOT change as a result of the update call, if you want the object to be updated with the
       actual values from the database, call "discard_changes" after the update.

         $row->update()->discard_changes();

       To determine before calling this method, which column values have changed and will be updated, call
       "get_dirty_columns".

       To check if any columns will be updated, call "is_changed".

       To force a column to be updated, call "make_column_dirty" before this method.

   delete
         $row->delete

       Arguments: none
       Returns: The Row object

       Throws an exception if the object is not in the database according to "in_storage". Also throws an
       exception if a proper WHERE clause uniquely identifying the database row can not be constructed (see
       significance of primary keys for more details).

       The object is still perfectly usable, but "in_storage" will now return 0 and the object must be
       reinserted using "insert" before it can be used to "update" the row again.

       If you delete an object in a class with a "has_many" relationship, an attempt is made to delete all
       the related objects as well. To turn this behaviour off, pass "cascade_delete => 0" in the $attr
       hashref of the relationship, see DBIx::Class::Relationship. Any database-level cascade or restrict
       will take precedence over a DBIx-Class-based cascading delete, since DBIx-Class deletes the main row
       first and only then attempts to delete any remaining related rows.

       If you delete an object within a txn_do() (see "txn_do" in DBIx::Class::Storage) and the transaction
       subsequently fails, the row object will remain marked as not being in storage. If you know for a fact
       that the object is still in storage (i.e. by inspecting the cause of the transaction's failure), you
       can use "$obj->in_storage(1)" to restore consistency between the object and the database. This would
       allow a subsequent "$obj->delete" to work as expected.

       See also "delete" in DBIx::Class::ResultSet.

   get_column
         my $val = $row->get_column($col);

       Arguments: $columnname
       Returns: The value of the column

       Throws an exception if the column name given doesn't exist according to "has_column".

       Returns a raw column value from the row object, if it has already been fetched from the database or
       set by an accessor.

       If an inflated value has been set, it will be deflated and returned.

       Note that if you used the "columns" or the "select/as" search attributes on the resultset from which
       $row was derived, and did not include $columnname in the list, this method will return "undef" even
       if the database contains some value.

       To retrieve all loaded column values as a hash, use "get_columns".

   has_column_loaded
         if ( $row->has_column_loaded($col) ) {
            print "$col has been loaded from db";
         }

       Arguments: $columnname
       Returns: 0|1

       Returns a true value if the column value has been loaded from the database (or set locally).

   get_columns
         my %data = $row->get_columns;

       Arguments: none
       Returns: A hash of columnname, value pairs.

       Returns all loaded column data as a hash, containing raw values. To get just one value for a
       particular column, use "get_column".

       See "get_inflated_columns" to get the inflated values.

   get_dirty_columns
         my %data = $row->get_dirty_columns;

       Arguments: none
       Returns: A hash of column, value pairs

       Only returns the column, value pairs for those columns that have been changed on this object since
       the last "update" or "insert" call.

       See "get_columns" to fetch all column/value pairs.

   make_column_dirty
         $row->make_column_dirty($col)

       Arguments: $columnname
       Returns: undefined

       Throws an exception if the column does not exist.

       Marks a column as having been changed regardless of whether it has really changed.

   get_inflated_columns
         my %inflated_data = $obj->get_inflated_columns;

       Arguments: none
       Returns: A hash of column, object|value pairs

       Returns a hash of all column keys and associated values. Values for any columns set to use inflation
       will be inflated and returns as objects.

       See "get_columns" to get the uninflated values.

       See DBIx::Class::InflateColumn for how to setup inflation.

   set_column
         $row->set_column($col => $val);

       Arguments: $columnname, $value
       Returns: $value

       Sets a raw column value. If the new value is different from the old one, the column is marked as
       dirty for when you next call "update".

       If passed an object or reference as a value, this method will happily attempt to store it, and a
       later "insert" or "update" will try and stringify/numify as appropriate. To set an object to be
       deflated instead, see "set_inflated_columns".

   set_columns
         $row->set_columns({ $col => $val, ... });

       Arguments: \%columndata
       Returns: The Row object

       Sets multiple column, raw value pairs at once.

       Works as "set_column".

   set_inflated_columns
         $row->set_inflated_columns({ $col => $val, $relname => $obj, ... });

       Arguments: \%columndata
       Returns: The Row object

       Sets more than one column value at once. Any inflated values are deflated and the raw values stored.

       Any related values passed as Row objects, using the relation name as a key, are reduced to the
       appropriate foreign key values and stored. If instead of related row objects, a hashref of column,
       value data is passed, will create the related object first then store.

       Will even accept arrayrefs of data as a value to a "has_many" in DBIx::Class::Relationship key, and
       create the related objects if necessary.

       Be aware that the input hashref might be edited in place, so don't rely on it being the same after a
       call to "set_inflated_columns". If you need to preserve the hashref, it is sufficient to pass a
       shallow copy to "set_inflated_columns", e.g. ( { %{ $href } } )

       See also "set_from_related" in DBIx::Class::Relationship::Base.

   copy
         my $copy = $orig->copy({ change => $to, ... });

       Arguments: \%replacementdata
       Returns: The Row object copy

       Inserts a new row into the database, as a copy of the original object. If a hashref of replacement
       data is supplied, these will take precedence over data in the original. Also any columns which have
       the column info attribute "is_auto_increment => 1" are explicitly removed before the copy, so that
       the database can insert its own autoincremented values into the new object.

       Relationships will be followed by the copy procedure only if the relationship specifies a true value
       for its cascade_copy attribute. "cascade_copy" is set by default on "has_many" relationships and
       unset on all others.

   store_column
         $row->store_column($col => $val);

       Arguments: $columnname, $value
       Returns: The value sent to storage

       Set a raw value for a column without marking it as changed. This method is used internally by
       "set_column" which you should probably be using.

       This is the lowest level at which data is set on a row object, extend this method to catch all data
       setting methods.

   inflate_result
         Class->inflate_result($result_source, \%me, \%prefetch?)

       Arguments: $result_source, \%columndata, \%prefetcheddata
       Returns: A Row object

       All DBIx::Class::ResultSet methods that retrieve data from the database and turn it into row objects
       call this method.

       Extend this method in your Result classes to hook into this process, for example to rebless the
       result into a different class.

       Reblessing can also be done more easily by setting "result_class" in your Result class. See
       "result_class" in DBIx::Class::ResultSource.

       Different types of results can also be created from a particular DBIx::Class::ResultSet, see
       "result_class" in DBIx::Class::ResultSet.

   update_or_insert
         $row->update_or_insert

       Arguments: none
       Returns: Result of update or insert operation

       "Update"s the object if it's already in the database, according to "in_storage", else "insert"s it.

   insert_or_update
         $obj->insert_or_update

       Alias for "update_or_insert"

   is_changed
         my @changed_col_names = $row->is_changed();
         if ($row->is_changed()) { ... }

       Arguments: none
       Returns: 0|1 or @columnnames

       In list context returns a list of columns with uncommited changes, or in scalar context returns a
       true value if there are uncommitted changes.

   is_column_changed
         if ($row->is_column_changed('col')) { ... }

       Arguments: $columname
       Returns: 0|1

       Returns a true value if the column has uncommitted changes.

   result_source
         my $resultsource = $row->result_source;

       Arguments: $result_source_instance
       Returns: a ResultSource instance

       Accessor to the DBIx::Class::ResultSource this object was created from.

   register_column
         $column_info = { .... };
         $class->register_column($column_name, $column_info);

       Arguments: $columnname, \%columninfo
       Returns: undefined

       Registers a column on the class. If the column_info has an 'accessor' key, creates an accessor named
       after the value if defined; if there is no such key, creates an accessor with the same name as the
       column

       The column_info attributes are described in "add_columns" in DBIx::Class::ResultSource

   get_from_storage
         my $copy = $row->get_from_storage($attrs)

       Arguments: \%attrs
       Returns: A Row object

       Fetches a fresh copy of the Row object from the database and returns it.  Throws an exception if a
       proper WHERE clause identifying the database row can not be constructed (i.e. if the original object
       does not contain its entire
        primary key ). If passed the \%attrs argument, will first apply these attributes to the resultset
       used to find the row.

       This copy can then be used to compare to an existing row object, to determine if any changes have
       been made in the database since it was created.

       To just update your Row object with any latest changes from the database, use "discard_changes"
       instead.

       The \%attrs argument should be compatible with "ATTRIBUTES" in DBIx::Class::ResultSet.

   discard_changes ($attrs?)
         $row->discard_changes

       Arguments: none or $attrs
       Returns: self (updates object in-place)

       Re-selects the row from the database, losing any changes that had been made. Throws an exception if a
       proper "WHERE" clause identifying the database row can not be constructed (i.e. if the original
       object does not contain its entire primary key).

       This method can also be used to refresh from storage, retrieving any changes made since the row was
       last read from storage.

       $attrs, if supplied, is expected to be a hashref of attributes suitable for passing as the second
       argument to "$resultset->search($cond, $attrs)";

       Note: If you are using DBIx::Class::Storage::DBI::Replicated as your storage, please kept in mind
       that if you "discard_changes" on a row that you just updated or created, you should wrap the entire
       bit inside a transaction.  Otherwise you run the risk that you insert or update to the master
       database but read from a replicant database that has not yet been updated from the master.  This will
       result in unexpected results.

   throw_exception
       See "throw_exception" in DBIx::Class::Schema.

   id
         my @pk = $row->id;

       Arguments: none
       Returns: A list of primary key values

       Returns the primary key(s) for a row. Can't be called as a class method.  Actually implemented in
       DBIx::Class::PK

AUTHORS
       Matt S. Trout <mst@shadowcatsystems.co.uk>

LICENSE
       You may distribute this code under the same terms as Perl itself.



perl v5.12.5                                     2011-07-27                              DBIx::Class::Row(3)