Modware

DBH

   Modware::DBH - Global database connection object.  Use for commits, rollbacks, custom SQL.

   # USE CASE: PERFORM A DATABASE TRANSACTION WITH ROLLBACK ON ERROR
   my $dbh = new Modware::DBH;
   eval {
      my $feature = new Modware::Feature( -primary_id => 'DDB0191090' );
      $feature->description('abc');

     # some more error prone code

   };
   if ($@){
      warn $@;

     # ROLLBACK WILL BE ISSUED ON ALL DATABASE CHANGES INVOLVING Modware OR
     # A DATABASE HANDLE CREATED WITH my $dbh = new Modware::DBH
      $dbh->rollback();
   }

   This is a singleton class: every call to 'new Modware::DBH' will return the same
   database handle: that used by Chado::AutoDBI

   Use this class to issue direct sql against the database and also for commits and rollbacks.

   You normally will not have to commit though since destructor for this class issues a commit 
   on unloading.

Methods description

 Title    : _insert_primary_id
 Usage    : $feature->_insert_primary_id;
 Function : inserts and links primary_id to feature
 Returns  : Chado::Dbxref object
 Args     : none

Methods code

   my ($class, @args) = @_;
   my $dbh = new Modware::DBH;
   $sth = $dbh->prepare("select nextval('feature_uniquename_seq')");
   $sth->execute();
   my $return = $sth->fetchrow();
   $sth->finish();
   return $return;

   my ( $self, $prefix ) = @_;

   # prefix should be passed in, but a default is the $ENV{'IDENTIFIER_PREFIX'}
   # from config.xml
   $prefix ||= $ENV{'IDENTIFIER_PREFIX'};

   my $number = Chado::Feature->next_unique_name();
      $number = sprintf("%08d", $number);
   my $new_id = $ENV{'IDENTIFIER_PREFIX'};
      $new_id.= $number;

  # created the dbxref
   my $dbxref = Chado::Dbxref->find_or_create(
      db_id     => Modware::Constant->Application_db_id(),
      accession => $new_id
   );

  return $dbxref;

   Chado::DBI->db_Main();

General documentation

   Eric Just e-just@northwestern.edu

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

Copyright © 2006, Northwestern University All rights reserved.