# $Id$

The bioperl-db package contains interfaces and adaptors that work 
with a BioSQL database and serialize and de-serialize Bioperl
objects.

===================================================================
Information about BioSQL and bioperl-db
===================================================================

This project was started by Ewan Birney with major work by Elia Stupka
and continued support by Hilmar Lapp and the Bioperl community. It's 
purpose is to create a standalone sequence database with little 
external dependencies and tight integration with Bioperl. Support for 
more databases and bindings in Java and python by Biojava and
Biopython projects is welcomed, and a working prototype was one of 
the accomplishments of the February 2002 hackathon in South Africa. 
All questions and comments should be directed to the bioperl list
<bioperl-l@bioperl.org> and more information can be found about the
related projects at http://www.bioperl.org and http://www.open-bio.org.

I. Scripts located in the scripts/ directory:

biosql/load_seqdatabase.pl      - a very flexible script to load
			          sequences into a BioSQL database
biosql/bioentry2flat.pl         - dump sequence data into rich sequence
		                  format flatfile from a BioSQL database
biosql/load_ontology.pl         - load GO or SOFA ontology data into
                                  a BioSQL database
biosql/merge-unique-ann.pl      - script used by load_seqdatabase.pl,
                                  it merges features and annotations
biosql/update-on-new-date.pl    - script used by load_seqdatabase.pl,
                                  it will update based on date
biosql/update-on-new-version.pl - script used by load_seqdatabase.pl,
			          it will update based on version
biosql/cgi-bin/getentry.pl      - example CGI script that fetches from
                                  a BioSQL database
biosql/clean_ontology.pl        - "cleans" an ontology in a BioSQL
                                  database without foreign keys
biosql/del-assocs-sql.pl        - script used by load-seqdatabase.pl,
                                  removes annotations and features 
biosql/freshen-annot.pl         - script used by load-seqdatabase.pl,
                                  removes annotations and features
biosql/load_interpro.pl         - deprecated
biosql/terms/add-term-annot.pl  - load ontology terms read from a file
biosql/terms/importrelation.pl  - load relations between ontology
			          terms and bioentries
biosql/terms/interpro2go.pl     - load from interpro2go file
corba/caching_corba_server.pl   - setup a corba sequence caching server
corba/test_bioenv.pl            - test the bioenv of a running server
corba/bioenv_server.pl          - setup a CORBA sequence server

There is also a script called scripts/load_ncbi_taxonomy.pl in the 
BioSQL package that loads taxonomic data from NCBI. Most users use
this script to load the NCBI taxonomy into their Biosql databases
before loading sequences with load_seqdatabase.pl.

II. Some background information and how it all works:

The adaptor code in Bio::DB and Bio::DB::BioSQL was completely
refactored and architected from scratch since the previous branch
bioperl-release-1-1-0. Meanwhile almost everything works. The
following things are unsupported or do not work yet:

     - sub-seqfeatures
     - round-tripping fuzzy locations (they will be stored according
	  to their Bio::Location::CoordinatePolicyI interpretation)
     - Bio::Annotation::DBLink::optional_id

To understand the layout of the API and how you can interact with the
adaptors to formulate your own queries, here is what you should know
and read (i.e., read the PODs of all interfaces and modules named
below).

1) Bio::DB::BioDB acts as a factory of database adaptors, where a
database adaptor encapsulates an entire database, not a specific
object-relational mapping or table. It is similar Bio::SeqIO in
bioperl, where you specify a format and get back a parser for that 
format. Here you specify the database and get back a persistence 
factory for that database. Note that the only database really 
supported right now in this framework is BioSQL.

2) The persistence factory returned by Bio::DB::BioDB->new() will
implement Bio::DB::DBAdaptorI. It allows you to obtain a persistence
adaptor for an object at hand, and to turn an object into a persistent
object.

3) A persistent object will implement Bio::DB::PersistentObjectI. A
persistent object can be updated in and removed from the database. It
also knows about its primary key in the database once it has been
created or found in the database. A persistent object will still
implement all interfaces and all methods that the non-persistent base
object implements. E.g., a persistent sequence object will implement
Bio::DB::PersistentObjectI and Bio::PrimarySeqI (or Bio::SeqI).

4) A persistence adaptor will implement Bio::DB::PersistenceAdaptorI. 
Apart from actually implementing all the persistence methods for 
persistent objects, a persistence adaptor allows you to locate 
objects in the database by key and by query. You can
find_by_primary_key(), find_by_unique_key(), find_by_association(), 
and find_by_query(). The latter allows you to formulate object queries 
as Bio::DB::Query::BioQuery objects and retrieve the matching objects.

5) The guiding principle for the redesign of the adaptors was to
separate business logic from schema logic. While business logic is
largely driven by the object model (hence, by the bioperl object
model) and therefore is mostly independent from the schema, but
specific to the object model, the schema logic is driven by and
specific to the relational model. The schema logic will therefore need
to differ from one schema to another and even from one schema flavor
to another for very similar relational models, whereas the business
logic is unaffected by this.

This had two consequences. First, the user interacts with the adaptors
without knowing anything about the specific schema behind it. All
interaction takes place in object space. You construct queries by
specifying object slots and the values they should have or
match. Joins and associations are also specified on the object level
(cf. Bio::DB::Query::BioQuery). Internally, the respective drivers for
the particular schema translate those queries into schema-specific SQL
queries.

The second consequence was that every persistence adaptor is divided
into two layers, the persistence adaptor itself which does not contain
a single SQL phrase or query, and its schema-specific driver which
implements those functions which cannot be accomplished without
actually doing the concrete object-relational mapping.

===================================================================
Information about Bio::DB::Map modules and database interface
===================================================================

These modules have been deprecated and are no longer in the distribution.

