--
-- database_schema.sql
--
-- Version: $Revision$
--
-- Date:    $Date$
--
-- Copyright (c) 2002, Hewlett-Packard Company and Massachusetts
-- Institute of Technology.  All rights reserved.
-- 
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are
-- met:
-- 
-- - Redistributions of source code must retain the above copyright
-- notice, this list of conditions and the following disclaimer.
-- 
-- - Redistributions in binary form must reproduce the above copyright
-- notice, this list of conditions and the following disclaimer in the
-- documentation and/or other materials provided with the distribution.
-- 
-- - Neither the name of the Hewlett-Packard Company nor the name of the
-- Massachusetts Institute of Technology nor the names of their
-- contributors may be used to endorse or promote products derived from
-- this software without specific prior written permission.
-- 
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-- ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-- HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-- INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-- BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
-- OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
-- TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
-- USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
-- DAMAGE.
--
--
--
--
--   DSpace SQL schema
--
--   Authors:   Peter Breton, Robert Tansley, David Stuve, Daniel Chudnov,
--              Richard Jones
--
--   This file is used as-is to initialize a database. Therefore,
--   table and view definitions must be ordered correctly.
--
--   Caution: THIS IS POSTGRESQL-SPECIFIC:
--
--   * SEQUENCES are used for automatic ID generation
--   * FUNCTION getnextid used for automatic ID generation
--
--
--   To convert to work with another database, you need to ensure
--   an SQL function 'getnextid', which takes a table name as an
--   argument, will return a safe new ID to use to create a new
--   row in that table.

-------------------------------------------------------
-- Function for obtaining new IDs.
--
--   * The argument is a table name
--   * It returns a new ID safe to use for that table
--
--   The function reads the next value from the sequence
--   'tablename_seq'
-------------------------------------------------------
CREATE FUNCTION getnextid(VARCHAR(40)) RETURNS INTEGER AS
    'SELECT CAST (nextval($1 || ''_seq'') AS INTEGER) AS RESULT;' LANGUAGE SQL;


-------------------------------------------------------
-- Sequences for creating new IDs (primary keys) for
-- tables.  Each table must have a corresponding
-- sequence called 'tablename_seq'.
-------------------------------------------------------
CREATE SEQUENCE bitstreamformatregistry_seq;
CREATE SEQUENCE fileextension_seq;
CREATE SEQUENCE bitstream_seq;
CREATE SEQUENCE eperson_seq;
CREATE SEQUENCE epersongroup_seq;
CREATE SEQUENCE item_seq;
CREATE SEQUENCE bundle_seq;
CREATE SEQUENCE item2bundle_seq;
CREATE SEQUENCE bundle2bitstream_seq;
CREATE SEQUENCE dctyperegistry_seq;
CREATE SEQUENCE dcvalue_seq;
CREATE SEQUENCE community_seq;
CREATE SEQUENCE collection_seq;
CREATE SEQUENCE community2community_seq;
CREATE SEQUENCE community2collection_seq;
CREATE SEQUENCE collection2item_seq;
CREATE SEQUENCE resourcepolicy_seq;
CREATE SEQUENCE epersongroup2eperson_seq;
CREATE SEQUENCE handle_seq;
CREATE SEQUENCE workspaceitem_seq;
CREATE SEQUENCE workflowitem_seq;
CREATE SEQUENCE tasklistitem_seq;
CREATE SEQUENCE registrationdata_seq;
CREATE SEQUENCE subscription_seq;
CREATE SEQUENCE history_seq;
CREATE SEQUENCE historystate_seq;
CREATE SEQUENCE communities2item_seq;
CREATE SEQUENCE itemsbyauthor_seq;
CREATE SEQUENCE itemsbytitle_seq;
CREATE SEQUENCE itemsbydate_seq;
CREATE SEQUENCE itemsbydateaccessioned_seq;
CREATE SEQUENCE itemsbysubject_seq;
CREATE SEQUENCE epersongroup2workspaceitem_seq;
CREATE SEQUENCE metadataschemaregistry_seq;
CREATE SEQUENCE metadatafieldregistry_seq;
CREATE SEQUENCE metadatavalue_seq;

CREATE SEQUENCE group2group_seq;
CREATE SEQUENCE group2groupcache_seq;

-------------------------------------------------------
-- BitstreamFormatRegistry table
-------------------------------------------------------
CREATE TABLE BitstreamFormatRegistry
(
  bitstream_format_id INTEGER PRIMARY KEY,
  mimetype            VARCHAR(48),
  short_description   VARCHAR(128) UNIQUE,
  description         TEXT,
  support_level       INTEGER,
  -- Identifies internal types
  internal             BOOL
);

-------------------------------------------------------
-- FileExtension table
-------------------------------------------------------
CREATE TABLE FileExtension
(
  file_extension_id    INTEGER PRIMARY KEY,
  bitstream_format_id  INTEGER REFERENCES BitstreamFormatRegistry(bitstream_format_id),
  extension            VARCHAR(16)
);

-------------------------------------------------------
-- Bitstream table
-------------------------------------------------------
CREATE TABLE Bitstream
(
   bitstream_id            INTEGER PRIMARY KEY,
   bitstream_format_id     INTEGER REFERENCES BitstreamFormatRegistry(bitstream_format_id),
   name                    VARCHAR(256),
   size_bytes              BIGINT,
   checksum                VARCHAR(64),
   checksum_algorithm      VARCHAR(32),
   description             TEXT,
   user_format_description TEXT,
   source                  VARCHAR(256),
   internal_id             VARCHAR(256),
   deleted                 BOOL,
   store_number            INTEGER,
   sequence_id             INTEGER
);

-------------------------------------------------------
-- EPerson table
-------------------------------------------------------
CREATE TABLE EPerson
(
  eperson_id          INTEGER PRIMARY KEY,
  email               VARCHAR(64) UNIQUE,
  password            VARCHAR(64),
  firstname           VARCHAR(64),
  lastname            VARCHAR(64),
  can_log_in          BOOL,
  require_certificate BOOL,
  self_registered     BOOL,
  last_active         TIMESTAMP,
  sub_frequency       INTEGER,
  phone	              VARCHAR(32),
  netid               VARCHAR(64),
  language            VARCHAR(64)
);

-- index by email
CREATE INDEX eperson_email_idx ON EPerson(email);

-- index by netid
CREATE INDEX eperson_netid_idx ON EPerson(netid);

-------------------------------------------------------
-- EPersonGroup table
-------------------------------------------------------
CREATE TABLE EPersonGroup
(
  eperson_group_id INTEGER PRIMARY KEY,
  name             VARCHAR(256) UNIQUE
);

------------------------------------------------------
-- Group2Group table, records group membership in other groups
------------------------------------------------------
CREATE TABLE Group2Group
(
  id        INTEGER PRIMARY KEY,
  parent_id INTEGER REFERENCES EPersonGroup(eperson_group_id),
  child_id  INTEGER REFERENCES EPersonGroup(eperson_group_id)
);

------------------------------------------------------
-- Group2GroupCache table, is the 'unwound' hierarchy in
-- Group2Group.  It explicitly names every parent child
-- relationship, even with nested groups.  For example,
-- If Group2Group lists B is a child of A and C is a child of B,
-- this table will have entries for parent(A,B), and parent(B,C)
-- AND parent(A,C) so that all of the child groups of A can be
-- looked up in a single simple query
------------------------------------------------------
CREATE TABLE Group2GroupCache
(
  id        INTEGER PRIMARY KEY,
  parent_id INTEGER REFERENCES EPersonGroup(eperson_group_id),
  child_id  INTEGER REFERENCES EPersonGroup(eperson_group_id)
);

-------------------------------------------------------
-- Item table
-------------------------------------------------------
CREATE TABLE Item
(
  item_id         INTEGER PRIMARY KEY,
  submitter_id    INTEGER REFERENCES EPerson(eperson_id),
  in_archive      BOOL,
  withdrawn       BOOL,
  last_modified   TIMESTAMP WITH TIME ZONE,
  owning_collection INTEGER
);

-------------------------------------------------------
-- Bundle table
-------------------------------------------------------
CREATE TABLE Bundle
(
  bundle_id          INTEGER PRIMARY KEY,
  name               VARCHAR(16),  -- ORIGINAL | THUMBNAIL | TEXT 
  primary_bitstream_id	INTEGER REFERENCES Bitstream(bitstream_id)
);

-------------------------------------------------------
-- Item2Bundle table
-------------------------------------------------------
CREATE TABLE Item2Bundle
(
  id        INTEGER PRIMARY KEY,
  item_id   INTEGER REFERENCES Item(item_id),
  bundle_id INTEGER REFERENCES Bundle(bundle_id)
);

-- index by item_id
CREATE INDEX item2bundle_item_idx on Item2Bundle(item_id);

-------------------------------------------------------
-- Bundle2Bitstream table
-------------------------------------------------------
CREATE TABLE Bundle2Bitstream
(
  id           INTEGER PRIMARY KEY,
  bundle_id    INTEGER REFERENCES Bundle(bundle_id),
  bitstream_id INTEGER REFERENCES Bitstream(bitstream_id)
);

-- index by bundle_id
CREATE INDEX bundle2bitstream_bundle_idx ON Bundle2Bitstream(bundle_id);

-------------------------------------------------------
-- Metadata Tables and Sequences
-------------------------------------------------------
CREATE TABLE MetadataSchemaRegistry
(
  metadata_schema_id INTEGER PRIMARY KEY DEFAULT NEXTVAL('metadataschemaregistry_seq'),
  namespace          VARCHAR(256) UNIQUE,
  short_id           VARCHAR(32) UNIQUE
);

CREATE TABLE MetadataFieldRegistry
(
  metadata_field_id   INTEGER PRIMARY KEY DEFAULT NEXTVAL('metadatafieldregistry_seq'),
  metadata_schema_id  INTEGER NOT NULL REFERENCES MetadataSchemaRegistry(metadata_schema_id),
  element             VARCHAR(64),
  qualifier           VARCHAR(64),
  scope_note          TEXT
);

CREATE TABLE MetadataValue
(
  metadata_value_id  INTEGER PRIMARY KEY DEFAULT NEXTVAL('metadatavalue_seq'),
  item_id            INTEGER REFERENCES Item(item_id),
  metadata_field_id  INTEGER REFERENCES MetadataFieldRegistry(metadata_field_id),
  text_value         TEXT,
  text_lang          VARCHAR(24),
  place              INTEGER
);

-- Create a dcvalue view for backwards compatibilty
CREATE VIEW dcvalue AS
  SELECT MetadataValue.metadata_value_id AS "dc_value_id", MetadataValue.item_id,
    MetadataValue.metadata_field_id AS "dc_type_id", MetadataValue.text_value,
    MetadataValue.text_lang, MetadataValue.place
  FROM MetadataValue, MetadataFieldRegistry
  WHERE MetadataValue.metadata_field_id = MetadataFieldRegistry.metadata_field_id
  AND MetadataFieldRegistry.metadata_schema_id = 1;

-- An index for item_id - almost all access is based on
-- instantiating the item object, which grabs all values
-- related to that item
CREATE INDEX metadatavalue_item_idx ON MetadataValue(item_id);
CREATE INDEX metadatavalue_item_idx2 ON MetadataValue(item_id,metadata_field_id);
CREATE INDEX metadatafield_schema_idx ON MetadataFieldRegistry(metadata_schema_id);
  
-------------------------------------------------------
-- Community table
-------------------------------------------------------
CREATE TABLE Community
(
  community_id      INTEGER PRIMARY KEY,
  name              VARCHAR(128),
  short_description VARCHAR(512),
  introductory_text TEXT,
  logo_bitstream_id INTEGER REFERENCES Bitstream(bitstream_id),
  copyright_text    TEXT,
  side_bar_text     TEXT
);

-------------------------------------------------------
-- Collection table
-------------------------------------------------------
CREATE TABLE Collection
(
  collection_id     INTEGER PRIMARY KEY,
  name              VARCHAR(128),
  short_description VARCHAR(512),
  introductory_text TEXT,
  logo_bitstream_id INTEGER REFERENCES Bitstream(bitstream_id),
  template_item_id  INTEGER REFERENCES Item(item_id),
  provenance_description  TEXT,
  license           TEXT,
  copyright_text    TEXT,
  side_bar_text     TEXT,
  workflow_step_1   INTEGER REFERENCES EPersonGroup( eperson_group_id ),
  workflow_step_2   INTEGER REFERENCES EPersonGroup( eperson_group_id ),
  workflow_step_3   INTEGER REFERENCES EPersonGroup( eperson_group_id ),
  submitter         INTEGER REFERENCES EPersonGroup( eperson_group_id ),
  admin             INTEGER REFERENCES EPersonGroup( eperson_group_id)
);

-------------------------------------------------------
-- Community2Community table
-------------------------------------------------------
CREATE TABLE Community2Community
(
  id             INTEGER PRIMARY KEY,
  parent_comm_id INTEGER REFERENCES Community(community_id),
  child_comm_id  INTEGER REFERENCES Community(community_id)
);

-------------------------------------------------------
-- Community2Collection table
-------------------------------------------------------
CREATE TABLE Community2Collection
(
  id             INTEGER PRIMARY KEY,
  community_id   INTEGER REFERENCES Community(community_id),
  collection_id  INTEGER REFERENCES Collection(collection_id)
);

-- Index on community ID
CREATE INDEX Community2Collection_community_id_idx ON Community2Collection(community_id);
-- Index on collection ID
CREATE INDEX Community2Collection_collection_id_idx ON Community2Collection(collection_id);

-------------------------------------------------------
-- Collection2Item table
-------------------------------------------------------
CREATE TABLE Collection2Item
(
  id            INTEGER PRIMARY KEY,
  collection_id INTEGER REFERENCES Collection(collection_id),
  item_id       INTEGER REFERENCES Item(item_id)
);

-- index by collection_id
CREATE INDEX collection2item_collection_idx ON Collection2Item(collection_id);
-- and item_id
CREATE INDEX Collection2Item_item_id_idx ON Collection2Item( item_id );

-------------------------------------------------------
-- ResourcePolicy table
-------------------------------------------------------
CREATE TABLE ResourcePolicy
(
  policy_id            INTEGER PRIMARY KEY,
  resource_type_id     INTEGER,
  resource_id          INTEGER,
  action_id            INTEGER,
  eperson_id           INTEGER REFERENCES EPerson(eperson_id),
  epersongroup_id      INTEGER REFERENCES EPersonGroup(eperson_group_id),
  start_date           DATE,
  end_date             DATE
);

-- index by resource_type,resource_id - all queries by
-- authorization manager are select type=x, id=y, action=z
CREATE INDEX resourcepolicy_type_id_idx ON ResourcePolicy(resource_type_id,resource_id); 

-------------------------------------------------------
-- EPersonGroup2EPerson table
-------------------------------------------------------
CREATE TABLE EPersonGroup2EPerson
(
  id               INTEGER PRIMARY KEY,
  eperson_group_id INTEGER REFERENCES EPersonGroup(eperson_group_id),
  eperson_id       INTEGER REFERENCES EPerson(eperson_id)
);

-- Index by group ID (used heavily by AuthorizeManager)
CREATE INDEX epersongroup2eperson_group_idx on EPersonGroup2EPerson(eperson_group_id);


-------------------------------------------------------
-- Handle table
-------------------------------------------------------
CREATE TABLE Handle
(
  handle_id        INTEGER PRIMARY KEY,
  handle           VARCHAR(256) UNIQUE,
  resource_type_id INTEGER,
  resource_id      INTEGER
);

-- index by handle, commonly looked up
CREATE INDEX handle_handle_idx ON Handle(handle);
-- index by resource id and resource type id
CREATE INDEX handle_resource_id_and_type_idx ON handle(resource_id, resource_type_id);

-------------------------------------------------------
--  WorkspaceItem table
-------------------------------------------------------
CREATE TABLE WorkspaceItem
(
  workspace_item_id INTEGER PRIMARY KEY,
  item_id           INTEGER REFERENCES Item(item_id),
  collection_id     INTEGER REFERENCES Collection(collection_id),
  -- Answers to questions on first page of submit UI
  multiple_titles   BOOL,
  published_before  BOOL,
  multiple_files    BOOL,
  -- How for the user has got in the submit process
  stage_reached     INTEGER,
  page_reached      INTEGER
);

-------------------------------------------------------
--  WorkflowItem table
-------------------------------------------------------
CREATE TABLE WorkflowItem
(
  workflow_id    INTEGER PRIMARY KEY,
  item_id        INTEGER REFERENCES Item(item_id) UNIQUE,
  collection_id  INTEGER REFERENCES Collection(collection_id),
  state          INTEGER,
  owner          INTEGER REFERENCES EPerson(eperson_id),

  -- Answers to questions on first page of submit UI
  multiple_titles       BOOL,
  published_before      BOOL,
  multiple_files        BOOL
  -- Note: stage reached not applicable here - people involved in workflow
  -- can always jump around submission UI

);

-------------------------------------------------------
--  TasklistItem table
-------------------------------------------------------
CREATE TABLE TasklistItem
(
  tasklist_id	INTEGER PRIMARY KEY,
  eperson_id	INTEGER REFERENCES EPerson(eperson_id),
  workflow_id	INTEGER REFERENCES WorkflowItem(workflow_id)
);


-------------------------------------------------------
--  RegistrationData table
-------------------------------------------------------
CREATE TABLE RegistrationData
(
  registrationdata_id   INTEGER PRIMARY KEY,
  email                 VARCHAR(64) UNIQUE,
  token                 VARCHAR(48),
  expires		TIMESTAMP
);


-------------------------------------------------------
--  Subscription table
-------------------------------------------------------
CREATE TABLE Subscription
(
  subscription_id   INTEGER PRIMARY KEY,
  eperson_id        INTEGER REFERENCES EPerson(eperson_id),
  collection_id     INTEGER REFERENCES Collection(collection_id)
);


-------------------------------------------------------
--  History table
-------------------------------------------------------
CREATE TABLE History
(
  history_id           INTEGER PRIMARY KEY,
  -- When it was stored
  creation_date        TIMESTAMP,
  -- A checksum to keep INTEGERizations from being stored more than once
  checksum             VARCHAR(32) UNIQUE
);

-------------------------------------------------------
--  HistoryState table
-------------------------------------------------------
CREATE TABLE HistoryState
(
  history_state_id           INTEGER PRIMARY KEY,
  object_id                  VARCHAR(64)
);

-------------------------------------------------------------------------------
-- EPersonGroup2WorkspaceItem table
-------------------------------------------------------------------------------

CREATE TABLE epersongroup2workspaceitem 
(
  id integer DEFAULT nextval('epersongroup2workspaceitem_seq'),
  eperson_group_id integer REFERENCES EPersonGroup(eperson_group_id),
  workspace_item_id integer REFERENCES WorkspaceItem(workspace_item_id),
  CONSTRAINT epersongroup2item_pkey PRIMARY KEY (id)
);


------------------------------------------------------------
-- Browse subsystem tables and views
------------------------------------------------------------

-------------------------------------------------------
--  Communities2Item table
-------------------------------------------------------
CREATE TABLE Communities2Item
(
   id                      INTEGER PRIMARY KEY,
   community_id            INTEGER REFERENCES Community(community_id),
   item_id                 INTEGER REFERENCES Item(item_id)
);

-- Index by item_id for update/re-index
CREATE INDEX Communities2Item_item_id_idx ON Communities2Item( item_id );

-------------------------------------------------------
-- Community2Item view
------------------------------------------------------
CREATE VIEW Community2Item as
SELECT Community2Collection.community_id, Collection2Item.item_id 
FROM Community2Collection, Collection2Item
WHERE Collection2Item.collection_id   = Community2Collection.collection_id
;

-------------------------------------------------------
--  ItemsByAuthor table
-------------------------------------------------------
CREATE TABLE ItemsByAuthor
(
   items_by_author_id INTEGER PRIMARY KEY,
   item_id            INTEGER REFERENCES Item(item_id),
   author             TEXT,
   sort_author        TEXT
);

-- index by sort_author, of course!
CREATE INDEX sort_author_idx on ItemsByAuthor(sort_author);
-- And by item ID for updates/re-indexing
CREATE INDEX ItemsByAuthor_item_id_idx ON ItemsByAuthor(item_id);

-------------------------------------------------------
--  CollectionItemsByAuthor view
-------------------------------------------------------
CREATE VIEW CollectionItemsByAuthor as
SELECT Collection2Item.collection_id, ItemsByAuthor.* 
FROM ItemsByAuthor, Collection2Item
WHERE ItemsByAuthor.item_id = Collection2Item.item_id
;

-------------------------------------------------------
--  CommunityItemsByAuthor view
-------------------------------------------------------
CREATE VIEW CommunityItemsByAuthor as
SELECT Communities2Item.community_id, ItemsByAuthor.* 
FROM ItemsByAuthor, Communities2Item
WHERE ItemsByAuthor.item_id = Communities2Item.item_id
;

----------------------------------------
-- ItemsByTitle table
----------------------------------------
CREATE TABLE ItemsByTitle
(
   items_by_title_id  INTEGER PRIMARY KEY,
   item_id            INTEGER REFERENCES Item(item_id),
   title              TEXT,
   sort_title         TEXT
);

-- index by the sort_title
CREATE INDEX sort_title_idx on ItemsByTitle(sort_title);
-- And by item ID for updates/re-indexing
CREATE INDEX ItemsByTitle_item_id_idx ON ItemsByTitle(item_id);

-------------------------------------------------------
--  CollectionItemsByTitle view
-------------------------------------------------------
CREATE VIEW CollectionItemsByTitle as
SELECT Collection2Item.collection_id, ItemsByTitle.* 
FROM ItemsByTitle, Collection2Item
WHERE ItemsByTitle.item_id = Collection2Item.item_id
;

-------------------------------------------------------
--  CommunityItemsByTitle view
-------------------------------------------------------
CREATE VIEW CommunityItemsByTitle as
SELECT Communities2Item.community_id, ItemsByTitle.* 
FROM ItemsByTitle, Communities2Item
WHERE ItemsByTitle.item_id = Communities2Item.item_id
;

-------------------------------------------------------
--  ItemsByDate table
-------------------------------------------------------
CREATE TABLE ItemsByDate
(
   items_by_date_id   INTEGER PRIMARY KEY,
   item_id            INTEGER REFERENCES Item(item_id),
   date_issued        TEXT
);

-- sort by date
CREATE INDEX date_issued_idx on ItemsByDate(date_issued);
-- And by item ID for updates/re-indexing
CREATE INDEX ItemsByDate_item_id_idx ON ItemsByDate(item_id);

-------------------------------------------------------
--  CollectionItemsByDate view
-------------------------------------------------------
CREATE VIEW CollectionItemsByDate as
SELECT Collection2Item.collection_id, ItemsByDate.* 
FROM ItemsByDate, Collection2Item
WHERE ItemsByDate.item_id = Collection2Item.item_id
;

-------------------------------------------------------
--  CommunityItemsByDate view
-------------------------------------------------------
CREATE VIEW CommunityItemsByDate as
SELECT Communities2Item.community_id, ItemsByDate.* 
FROM ItemsByDate, Communities2Item
WHERE ItemsByDate.item_id = Communities2Item.item_id
;

-------------------------------------------------------
--  ItemsByDateAccessioned table
-------------------------------------------------------
CREATE TABLE ItemsByDateAccessioned
(
   items_by_date_accessioned_id  INTEGER PRIMARY KEY,
   item_id                       INTEGER REFERENCES Item(item_id),
   date_accessioned              TEXT
);

-- Index on item_id for update/re-indexing
CREATE INDEX ItemsByDateAccessioned_item_id_idx ON ItemsByDateAccessioned(item_id);

-------------------------------------------------------
--  CollectionItemsByDateAccession view
-------------------------------------------------------
CREATE VIEW CollectionItemsByDateAccession as
SELECT Collection2Item.collection_id, ItemsByDateAccessioned.* 
FROM ItemsByDateAccessioned, Collection2Item
WHERE ItemsByDateAccessioned.item_id = Collection2Item.item_id
;

-------------------------------------------------------
--  CommunityItemsByDateAccession view
-------------------------------------------------------
CREATE VIEW CommunityItemsByDateAccession as
SELECT Communities2Item.community_id, ItemsByDateAccessioned.* 
FROM ItemsByDateAccessioned, Communities2Item
WHERE ItemsByDateAccessioned.item_id = Communities2Item.item_id
;

-------------------------------------------------------
--  ItemsBySubject table
-------------------------------------------------------
CREATE TABLE ItemsBySubject
(
   items_by_subject_id INTEGER PRIMARY KEY,
   item_id             INTEGER REFERENCES Item(item_id),
   subject             TEXT,
   sort_subject        TEXT
);

-- index by sort_subject
CREATE INDEX sort_subject_idx on ItemsBySubject(sort_subject);

-------------------------------------------------------
--  CollectionItemsBySubject view
-------------------------------------------------------
CREATE VIEW CollectionItemsBySubject as
SELECT Collection2Item.collection_id, ItemsBySubject.* 
FROM ItemsBySubject, Collection2Item
WHERE ItemsBySubject.item_id = Collection2Item.item_id
;

-------------------------------------------------------
--  CommunityItemsBySubject view
-------------------------------------------------------
CREATE VIEW CommunityItemsBySubject as
SELECT Communities2Item.community_id, ItemsBySubject.* 
FROM ItemsBySubject, Communities2Item
WHERE ItemsBySubject.item_id = Communities2Item.item_id
;

-------------------------------------------------------------------------
-- Tables to manage cache of item counts for communities and collections
-------------------------------------------------------------------------

CREATE TABLE collection_item_count (
	collection_id INTEGER REFERENCES collection(collection_id),
	number INTEGER
);

CREATE TABLE community_item_count (
	community_id INTEGER REFERENCES community(community_id),
	number INTEGER
);

-------------------------------------------------------
--  Create 'special' groups, for anonymous access
--  and administrators
-------------------------------------------------------
-- We don't use getnextid() for 'anonymous' since the sequences start at '1'
INSERT INTO epersongroup VALUES(0, 'Anonymous');
INSERT INTO epersongroup VALUES(getnextid('epersongroup'), 'Administrator');


-------------------------------------------------------
-- Create the checksum checker tables
-------------------------------------------------------
-- list of the possible results as determined
-- by the system or an administrator

CREATE TABLE checksum_results
(
    result_code VARCHAR PRIMARY KEY,
    result_description VARCHAR
);


-- This table has a one-to-one relationship
-- with the bitstream table. A row will be inserted
-- every time a row is inserted into the bitstream table, and
-- that row will be updated every time the checksum is
-- re-calculated.

CREATE TABLE most_recent_checksum 
(
    bitstream_id INTEGER PRIMARY KEY REFERENCES bitstream(bitstream_id),
    to_be_processed BOOLEAN NOT NULL,
    expected_checksum VARCHAR NOT NULL,
    current_checksum VARCHAR NOT NULL,
    last_process_start_date TIMESTAMP NOT NULL,
    last_process_end_date TIMESTAMP NOT NULL,
    checksum_algorithm VARCHAR NOT NULL,
    matched_prev_checksum BOOLEAN NOT NULL,
    result VARCHAR REFERENCES checksum_results(result_code)
);

-- A row will be inserted into this table every
-- time a checksum is re-calculated.

CREATE TABLE checksum_history 
(
    check_id BIGSERIAL PRIMARY KEY,  
    bitstream_id INTEGER,
    process_start_date TIMESTAMP,
    process_end_date TIMESTAMP,
    checksum_expected VARCHAR,
    checksum_calculated VARCHAR,
    result VARCHAR REFERENCES checksum_results(result_code)
);


-- this will insert into the result code
-- the initial results that should be 
-- possible

insert into checksum_results
values
( 
    'INVALID_HISTORY',
    'Install of the cheksum checking code do not consider this history as valid' 
);

insert into checksum_results
values
( 
    'BITSTREAM_NOT_FOUND',
    'The bitstream could not be found' 
);

insert into checksum_results
values
( 
    'CHECKSUM_MATCH',
    'Current checksum matched previous checksum' 
);

insert into checksum_results
values
(
    'CHECKSUM_NO_MATCH',
    'Current checksum does not match previous checksum' 
);

insert into checksum_results
values
( 
    'CHECKSUM_PREV_NOT_FOUND',
    'Previous checksum was not found: no comparison possible' 
);

insert into checksum_results
values
( 
    'BITSTREAM_INFO_NOT_FOUND',
    'Bitstream info not found' 
);

insert into checksum_results
values
( 
    'CHECKSUM_ALGORITHM_INVALID',
    'Invalid checksum algorithm' 
);
insert into checksum_results
values
( 
    'BITSTREAM_NOT_PROCESSED',
    'Bitstream marked to_be_processed=false' 
);
insert into checksum_results
values
( 
    'BITSTREAM_MARKED_DELETED',
    'Bitstream marked deleted in bitstream table' 
);