Bio::DB::Biblio::eutils(3) Access to PubMed's bibliographic query service

SYNOPSIS

Do not use this object directly, it is recommended to access it and use it through the Bio::Biblio module:


use Bio::Biblio;
use Bio::Biblio::IO;
my $biblio = Bio::Biblio->new( -access => 'eutils' );
$biblio->find("10336996");
my $xml = $biblio->get_next;
my $io = Bio::Biblio::IO->new( -data => $xml,
-format => 'medlinexml' );
my $article = $io->next_bibref();

DESCRIPTION

This object contains the real implementation of a Bibliographic Query Service as defined in Bio::DB::BiblioI.

Bio::DB::BiblioI is not implemented as documented in the interface, particularly the find() method, which is not compatible with PubMed's query language.

FEEDBACK

Mailing Lists

User feedback is an integral part of the evolution of this and other Bioperl modules. Send your comments and suggestions preferably to the Bioperl mailing list. Your participation is much appreciated.

  [email protected]                  - General discussion
  http://bioperl.org/wiki/Mailing_lists  - About the mailing lists

Support

Please direct usage questions or support issues to the mailing list:

[email protected]

rather than to the module maintainer directly. Many experienced and reponsive experts will be able look at the problem and quickly address it. Please include a thorough description of the problem with code and data examples if at all possible.

Reporting Bugs

Report bugs to the Bioperl bug tracking system to help us keep track of the bugs and their resolution. Bug reports can be submitted via the web:

  https://redmine.open-bio.org/projects/bioperl/

AUTHOR

Allen Day <[email protected]>

COPYRIGHT

Copyright (c) 2004 Allen Day, University of California, Los Angeles.

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

DISCLAIMER

This software is provided ``as is'' without warranty of any kind.

BUGS AND LIMITATIONS

  • More testing and debugging needed to ensure that returned citations are properly transferred even if they contain foreign characters.
  • Maximum record count (MAX_RECORDS) returned currently hard coded to 100K.
  • Biblio retrieval methods should be more tightly integrated with Bio::Biblio::Ref and Bio::DB::MeSH.

APPENDIX

The main documentation details are to be found in Bio::DB::BiblioI.

Here is the rest of the object methods. Interface methods first, followed by internal methods.

_initialize

 Usage   : my $obj = Bio::Biblio->new(-access => 'eutils' ...);
           (_initialize is internally called from this constructor)
 Returns : 1 on success
 Args    : none

This is an actual new() method (except for the real object creation and its blessing which is done in the parent class Bio::Root::Root in method _create_object).

Note that this method is called always as an object method (never as a class method) - and that the object who calls this method may already be partly initiated (from Bio::Biblio::new method); so if you need to do some tricks with the 'class invocation' you need to change Bio::Biblio::new method, not this one.

db

 Title   : db
 Usage   : $obj->db($newval)
 Function: specifies the database to search.  valid values are:
           pubmed, pmc, journals
           it is also possible to add the following, and i will do
           so on request:
           genome, nucleotide, protein, popset, snp, sequence, taxonomy
           pubmed is default.
 Returns : value of db (a scalar)
 Args    : on set, new value (a scalar or undef, optional)

Methods implementing Bio::DB::BiblioI interface

get_collection_id

  Title   : get_collection_id
  Usage   : $id = $biblio->get_collection_id();
  Function: returns WebEnv value from ESearch
  Returns : ESearch WebEnv value as a string
  Args    : none

reset_retrieval

  Title   : reset_retrieval
  Usage   : $biblio->reset_retrieval();
  Function: reset cursor in id list, see cursor()
  Returns : 1
  Args    : none

get_next

  Title   : get_next
  Usage   : $xml = $biblio->get_next();
  Function: return next record as xml
  Returns : an xml string
  Args    : none

get_more

  Title   : get_more
  Usage   : $xml = $biblio->get_more($more);
  Function: returns next $more records concatenated
  Returns : a string containing multiple xml documents
  Args    : an integer representing how many records to retrieve

has_next

  Title   : has_next
  Usage   : $has_next = $biblio->has_next();
  Function: check to see if there are more items to be retrieved
  Returns : 1 on true, undef on false
  Args    : none

find

  Title   : find
  Usage   : $biblio = $biblio->find($pubmed_query_phrase);
  Function: perform a PubMed query using Entrez ESearch
  Returns : a reference to the object on which the method was called
  Args    : a PubMed query phrase.  See
            http://eutils.ncbi.nlm.nih.gov/entrez/query/static/help/pmhelp.html
            for help on how to construct a query.

get_all_ids

  Title   : get_all_ids
  Usage   : @ids = $biblio->get_all_ids();
  Function: return a list of PubMed ids resulting from call to find()
  Returns : a list of PubMed ids, or an empty list
  Args    : none

get_all

  Title   : get_all
  Usage   : $xml = $biblio->get_all();
  Function: retrieve all records from query
  Returns : return a large concatenated string of PubMed xml documents
  Args    : none

exists

  Title   : exists
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

destroy

  Title   : destroy
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

get_vocabulary_names

  Title   : get_vocabulary_names
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : empty arrayref
  Args    : none

contains

  Title   : contains
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

get_entry_description

  Title   : get_entry_description
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

get_all_values

  Title   : get_all_values
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

get_all_entries

  Title   : get_all_entries
  Usage   : do not use
  Function: no-op.  this is here only for interface compatibility
  Returns : undef
  Args    : none

Internal methods unrelated to Bio::DB::BiblioI

cursor

  Title   : cursor
  Usage   : $obj->cursor($newval)
  Function: holds position in reference collection
  Returns : value of cursor (a scalar)
  Args    : on set, new value (a scalar or undef, optional)

twig

  Title   : twig
  Usage   : $obj->twig($newval)
  Function: holds an XML::Twig instance.
  Returns : value of twig (a scalar)
  Args    : on set, new value (a scalar or undef, optional)

ids

  Title   : ids
  Usage   : $obj->ids($newval)
  Function: store pubmed ids resulting from find() query
  Returns : value of ids (a scalar)
  Args    : on set, new value (a scalar or undef, optional)

collection_id

  Title   : collection_id
  Usage   : $obj->collection_id($newval)
  Function:
  Returns : value of collection_id (a scalar)
  Args    : on set, new value (a scalar or undef, optional)

count

  Title   : count
  Usage   : $obj->count($newval)
  Function:
  Returns : value of count (a scalar)
  Args    : on set, new value (a scalar or undef, optional)

query_key

  Title   : query_key
  Usage   : $obj->query_key($newval)
  Function: holds query_key from ESearch document
  Returns : value of query_key (a scalar)
  Args    : on set, new value (a scalar or undef, optional)