Bio::DB::Query::DBQueryResult - DESCRIPTION of Object


Give standard usage here


This modules provides an implementation of Bio::DB::Query::QueryResultI for database queries through DBI.


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AUTHOR - Hilmar Lapp

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The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _


 Title   : new
 Usage   : my $obj = Bio::DB::Query::DBQueryResult->new();
 Function: Builds a new Bio::DB::Query::DBQueryResult object 
 Returns : an instance of Bio::DB::Query::DBQueryResult
 Args    : named parameters

           -sth        the statement handle (this object will not
                       execute it)

           -adaptor    the persistence adaptor (basically needs to 
                       implement instantiate_from_row($row, $factory)

           -factory    optionally, the object factory to pass to the

           -num_fks    the number of foreign key object columns in
                       the rows

           -flat_only  whether to retrieve and attach children when
                       building objects (default: false)

           If none of these are given at instantiation, at least sth() and
           persistence_adaptor() must be set prior to calling next_object().


 Title   : next_object
 Usage   :
 Function: Obtain the next object from the result stream and return it.
 Example :
 Returns : A Bioperl object (implementing at least Bio::Root::RootI)
 Args    : none


 Title   : each_Object
 Usage   :
 Function: This is primarily a convenience method and in most implementations
           will just loop over next_object() and return an array of all
 Example :
 Returns : A reference to an array of objects.
 Args    : Optionally, an anonymous function for filtering objects. If given,
           the function is passed one argument, the object to evaluate.
           The object will be included in the returned array if the function
           returns TRUE, and rejected otherwise.


 Title   : finish
 Usage   :
 Function: Indicate being finished with this result so that possibly used
           system resources can be released.
 Example :
 Returns : none
 Args    : none


 Title   : sth
 Usage   : $obj->sth($newval)
 Function: Get/set statement handle from which to fetch the next row.

           This can be changed at any time. If changed, it means the next
           call to next_object() will fetch from the new handle. Also, the
           caller needs to finish() the previous handle if necessary (i.e.,
           if not exhausted).

           Note that this object will not execute the statement handle. The
           caller needs to ensure that has been happened until next_object()
           is called.
 Example : 
 Returns : value of sth (a DBI statement handle)
 Args    : new value (a DBI statement handle, optional)


 Title   : persistence_adaptor
 Usage   : $obj->persistence_adaptor($newval)
 Function: Get/set the instantiation adaptor to which to delegate object
           instantiation from an array of row values.

           The adaptor can be any object that implements instantiate_from_row()
           with two arguments, a reference to an array of column values, and
           optionally an object factory.

           This can be changed at any time with no adverse side effect other
           than the kind of object built possibly changing.
 Example : 
 Returns : value of persistence_adaptor (an object)
 Args    : new value (an object, optional)


 Title   : object_factory
 Usage   : $obj->object_factory($newval)
 Function: Get/set the object factory to pass to the instantiation adaptor.

           Setting this is optional because providing it to the instantiation
           adaptor is optional.
 Example : 
 Returns : value of object_factory (a Bio::Factory::ObjectFactoryI compliant
 Args    : new value (a Bio::Factory::ObjectFactoryI compliant
           instance, optional)


 Title   : num_fks
 Usage   : $obj->num_fks($newval)
 Function: Get/set the number of foreign key columns in a given result row.

           Setting this correctly is only important for query results for which
           the resulting objects must have the foreign key objects attached.
 Example : 
 Returns : value of num_fks (a scalar)
 Args    : new value (a scalar, optional)


 Title   : flat_retrieval
 Usage   : $obj->flat_retrieval($newval)
 Function: Get/set whether objects should be retrieved and built flat
           or with all their dependent objects fetched and attached.

           The default is to build full objects with all children
           attached which provides for no bad surprises when
           inspecting the results. However, building flat objects by
           disregarding children is potentially a lot faster, so this
           option is useful if, for instance, for a sequence you don't
           need any annotation or features.

 Example : 
 Returns : value of flat_retrieval (a scalar evaluating to true or false)
 Args    : on set, new value (a scalar or undef, optional)