-- -- acs-kernel/sql/acs-metadata-create.sql -- -- A generic metadata system that allows table inheritence. This is -- based in many ways on Problem Set 4 by Philip Greenspun -- (philg@mit.edu), and the user-groups data model by Tracy Adams -- (teadams@mit.edu). -- -- @author Michael Yoon (michael@arsdigita.com) -- @author Rafael Schloming (rhs@mit.edu) -- @author Jon Salz (jsalz@mit.edu) -- -- @creation-date 2000-05-18 -- -- @cvs-id $Id: acs-metadata-create.sql,v 1.5 2002/09/16 21:52:41 jeffd Exp $ -- -- ****************************************************************** -- * KNOWLEDGE LEVEL -- ****************************************************************** ------------------ -- OBJECT TYPES -- ------------------ create table acs_object_types ( object_type varchar2(1000) not null constraint acs_object_types_pk primary key, supertype constraint acs_object_types_supertype_fk references acs_object_types (object_type), abstract_p char(1) default 'f' not null constraint acs_obj_types_abstract_p_ck check (abstract_p in ('t', 'f')), pretty_name varchar2(1000) not null constraint acs_obj_types_pretty_name_un unique, pretty_plural varchar2(1000) not null constraint acs_obj_types_pretty_plural_un unique, table_name varchar2(30) not null constraint acs_object_types_table_name_un unique, id_column varchar2(30) not null, package_name varchar2(30) not null constraint acs_object_types_pkg_name_un unique, name_method varchar2(100), type_extension_table varchar2(30), dynamic_p char(1) default 'f' constraint acs_obj_types_dynamic_p_ck check (dynamic_p in ('t', 'f')) ); -- create bitmap index acs_obj_types_supertype_idx on acs_object_types (supertype); create index acs_obj_types_supertype_idx on acs_object_types (supertype); comment on table acs_object_types is ' Each row in the acs_object_types table represents a distinct class of objects. For each instance of any acs_object_type, there is a corresponding row in the acs_objects table. Essentially, acs_objects.object_id supersedes the on_which_table/on_what_id pair that ACS 3.x used as the system-wide identifier for heterogeneous objects. The value of having a system-wide identifier for heterogeneous objects is that it helps us provide general solutions for common problems like access control, workflow, categorppization, and search. (Note that this framework is not overly restrictive, because it doesn''t force every type of object to be represented in the acs_object_types table.) Each acs_object_type has: * Attributes (stored in the acs_attributes table) Examples: - the "user" object_type has "email" and "password" attributes - the "content_item" object_type has "title" and "body" attributes * Relationship types (stored in the acs_rel_types table) Examples: - "a team has one team leader who is a user" (in other words, instances of the "team" object_type must have one "team leader" relationship to an instance of the "user" object_type) - "a content item may have zero or authors who are people or organizations, i.e., parties" (in other words, instances of the "content_item" object_type may have zero or more "author" relationships to instances of the "party" object_type) Possible extensions include automatic versioning, logical deletion, and auditing. '; comment on column acs_object_types.supertype is ' The object_type of which this object_type is a specialization (if any). For example, the supertype of the "user" object_type is "person". An object_type inherits the attributes and relationship rules of its supertype, though it can add constraints to the attributes and/or it can override the relationship rules. For instance, the "person" object_type has an optional "email" attribute, while its "user" subtype makes "email" mandatory. '; comment on column acs_object_types.abstract_p is ' ... If the object_type is not abstract, then all of its attributes must have a non-null storage specified. '; comment on column acs_object_types.table_name is ' The name of the type-specific table in which the values of attributes specific to this object_type are stored, if any. '; comment on column acs_object_types.id_column is ' The name of the primary key column in the table identified by table_name. '; comment on column acs_object_types.name_method is ' The name of a stored function that takes an object_id as an argument and returns a varchar2: the corresponding object name. This column is required to implement the polymorphic behavior of the acs.object_name() function. '; comment on column acs_object_types.type_extension_table is ' Object types (and their subtypes) that require more type-specific data than the fields already existing in acs_object_types may name a table in which that data is stored. The table should be keyed by the associated object_type. For example, a row in the user_group_types table stores a default approval policy for every user group of that type. In this example, the user_group_types table has a primary key named group_type that references acs_object_types. If a subtype of user_groups for example, lab_courses, has its own type-specific data, it could be maintained in a table called lab_course_types, with a primary key named lab_course_type that references user_group_types. This provides the same functionality as static class fields in an object-oriented programming language. '; comment on column acs_object_types.dynamic_p is ' This flag is used to identify object types created dynamically (e.g. through a web interface). Dynamically created object types can be administered differently. For example, the group type admin pages only allow users to add attributes or otherwise modify dynamic object types. This column is still experimental and may not be supported in the future. That is the reason it is not yet part of the API. '; create or replace view acs_object_type_supertype_map as select ot.object_type, ota.object_type as ancestor_type from acs_object_types ot, acs_object_types ota where ota.object_type in (select object_type from acs_object_types start with object_type = ot.supertype connect by object_type = prior supertype); create table acs_object_type_tables ( object_type not null constraint acs_obj_type_tbls_obj_type_fk references acs_object_types (object_type), table_name varchar2(30) not null, id_column varchar2(30), constraint acs_object_type_tables_pk primary key (object_type, table_name) ); -- create bitmap index acs_objtype_tbls_objtype_idx on acs_object_type_tables (object_type); create index acs_objtype_tbls_objtype_idx on acs_object_type_tables (object_type); comment on table acs_object_type_tables is ' This table is used for objects that want to vertically partition their data storage, for example user_demographics stores a set of optional columns that belong to a user object. '; comment on column acs_object_type_tables.id_column is ' If this is null then the id column is assumed to have the same name as the primary table. '; ------------------------------------ -- DATATYPES AND ATTRIBUTES -- ------------------------------------ create table acs_datatypes ( datatype varchar2(50) not null constraint acs_datatypes_pk primary key, max_n_values integer default 1 constraint acs_datatypes_max_n_ck check (max_n_values > 0) ); comment on table acs_datatypes is ' Defines the set of available datatypes for acs_attributes. These datatypes are abstract, not implementation-specific, i.e., they are not Oracle datatypes. The set of pre-defined datatypes is inspired by XForms (http://www.w3.org/TR/xforms-datamodel/). '; comment on column acs_datatypes.max_n_values is ' The maximum number of values that any attribute with this datatype can have. Of the predefined attribute types, only "boolean" specifies a non-null max_n_values, because it doesn''t make sense to have a boolean attribute with more than one value. There is no corresponding min_n_values column, because each attribute may be optional, i.e., min_n_values would always be zero. '; -- Load pre-defined datatypes. -- begin insert into acs_datatypes (datatype, max_n_values) values ('string', null); insert into acs_datatypes (datatype, max_n_values) values ('boolean', 1); insert into acs_datatypes (datatype, max_n_values) values ('number', null); insert into acs_datatypes (datatype, max_n_values) values ('integer', 1); insert into acs_datatypes (datatype, max_n_values) values ('money', null); insert into acs_datatypes (datatype, max_n_values) values ('date', null); insert into acs_datatypes (datatype, max_n_values) values ('timestamp', null); insert into acs_datatypes (datatype, max_n_values) values ('time_of_day', null); insert into acs_datatypes (datatype, max_n_values) values ('enumeration', null); commit; end; / --create table acs_input_types ( --); create sequence acs_attribute_id_seq; create table acs_attributes ( attribute_id integer not null constraint acs_attributes_pk primary key, object_type not null constraint acs_attributes_object_type_fk references acs_object_types (object_type), table_name varchar2(30), constraint acs_attrs_obj_type_tbl_name_fk foreign key (object_type, table_name) references acs_object_type_tables, attribute_name varchar2(100) not null, pretty_name varchar2(100) not null, pretty_plural varchar2(100), sort_order integer not null, datatype not null constraint acs_attributes_datatype_fk references acs_datatypes (datatype), default_value varchar2(4000), min_n_values integer default 1 not null constraint acs_attributes_min_n_ck check (min_n_values >= 0), max_n_values integer default 1 not null constraint acs_attributes_max_n_ck check (max_n_values >= 0), storage varchar2(13) default 'type_specific' constraint acs_attributes_storage_ck check (storage in ('type_specific', 'generic')), static_p varchar2(1) default 'f' constraint acs_attributes_static_bool check (static_p in ('t', 'f')), column_name varchar2(30), constraint acs_attributes_attr_name_un unique (attribute_name, object_type), constraint acs_attributes_pretty_name_un unique (pretty_name, object_type), constraint acs_attributes_sort_order_un unique (attribute_id, sort_order), constraint acs_attributes_n_values_ck check (min_n_values <= max_n_values) ); -- constraint acs_attrs_pretty_plural_un -- unique (pretty_plural, object_type), -- create bitmap index acs_attrs_obj_type_idx on acs_attributes (object_type); create index acs_attrs_obj_type_idx on acs_attributes (object_type); create index acs_attrs_tbl_name_idx on acs_attributes (table_name); -- create bitmap index acs_attrs_datatype_idx on acs_attributes (datatype); create index acs_attrs_datatype_idx on acs_attributes (datatype); comment on table acs_attributes is ' Each row in the acs_attributes table defines an attribute of the specified object type. Each object of this type must have a minimum of min_n_values values and a maximum of max_n_values for this attribute. '; comment on column acs_attributes.table_name is ' If the data storage for the object type is arranged in a vertically partitioned manner, then this column should indicate in which table the attribute is stored. '; comment on column acs_attributes.storage is ' Indicates how values of this attribute are stored: either "type_specific" (i.e., in the table identified by object_type.table_name) or "generic" (i.e., in the acs_attribute_values table). (Or we could just have a column_name and, if it''s null, then assume that we''re using acs_attribute_values.) '; comment on column acs_attributes.static_p is ' Determines whether this attribute is static. If so, only one copy of the attribute''s value exists for all objects of the same type. This value is stored in acs_static_attr_values table if storage_type is "generic". Otherwise, each object of this type can have its own distinct value for the attribute. '; comment on column acs_attributes.column_name is ' If storage is "type_specific", column_name identifies the column in the table identified by object_type.table_name that holds the values of this attribute. If column_name is null, then we assume that attribute_name identifies a column in the table identified by object_type.table_name. '; create table acs_enum_values ( attribute_id not null constraint asc_enum_values_attr_id_fk references acs_attributes (attribute_id), enum_value varchar2(1000), pretty_name varchar2(100) not null, sort_order integer not null, constraint acs_enum_values_pk primary key (attribute_id, enum_value), constraint acs_enum_values_pretty_name_un unique (attribute_id, pretty_name), constraint acs_enum_values_sort_order_un unique (attribute_id, sort_order) ); create index acs_enum_values_attr_id_idx on acs_enum_values (attribute_id); create table acs_attribute_descriptions ( object_type not null constraint acs_attr_descs_obj_type_fk references acs_object_types (object_type), attribute_name varchar2(100) not null, constraint acs_attr_descs_ob_tp_at_na_fk foreign key (object_type, attribute_name) references acs_attributes (object_type, attribute_name), description_key varchar2(100), constraint acs_attribute_descriptions_pk primary key (object_type, attribute_name, description_key), description clob not null ); -- create bitmap index acs_attr_desc_obj_type_idx on acs_attribute_descriptions (object_type); create index acs_attr_desc_obj_type_idx on acs_attribute_descriptions (object_type); create index acs_attr_desc_attr_name_idx on acs_attribute_descriptions (attribute_name); -- Create a view to show us all the attributes for one object, -- including attributes for each of its supertypes -- Note that the internal union is required to get attributes for the -- object type we specify. Without this union, we would get attributes -- for all supertypes, but not for the specific type in question -- Note also that we cannot select attr.* in the view because the -- object_type in the attributes table refers to one attribute (kind -- of like the owner of the attribute). That object_type is really the -- ancestor type... that is, the ancestor of the user-specified object -- type for which the attribute should be specified. create or replace view acs_object_type_attributes as select all_types.object_type, all_types.ancestor_type, attr.attribute_id, attr.table_name, attr.attribute_name, attr.pretty_name, attr.pretty_plural, attr.sort_order, attr.datatype, attr.default_value, attr.min_n_values, attr.max_n_values, attr.storage, attr.static_p, attr.column_name from acs_attributes attr, (select map.object_type, map.ancestor_type from acs_object_type_supertype_map map, acs_object_types t where map.object_type=t.object_type UNION ALL select t.object_type, t.object_type as ancestor_type from acs_object_types t) all_types where attr.object_type = all_types.ancestor_type; ----------------------- -- METADATA PACKAGES -- ----------------------- create or replace package acs_object_type is -- define an object type procedure create_type ( object_type in acs_object_types.object_type%TYPE, pretty_name in acs_object_types.pretty_name%TYPE, pretty_plural in acs_object_types.pretty_plural%TYPE, supertype in acs_object_types.supertype%TYPE default 'acs_object', table_name in acs_object_types.table_name%TYPE, id_column in acs_object_types.id_column%TYPE default 'XXX', package_name in acs_object_types.package_name%TYPE default null, abstract_p in acs_object_types.abstract_p%TYPE default 'f', type_extension_table in acs_object_types.type_extension_table%TYPE default null, name_method in acs_object_types.name_method%TYPE default null ); -- delete an object type definition procedure drop_type ( object_type in acs_object_types.object_type%TYPE, cascade_p in char default 'f' ); -- look up an object type's pretty_name function pretty_name ( object_type in acs_object_types.object_type%TYPE ) return acs_object_types.pretty_name%TYPE; -- Returns 't' if object_type_2 is a subtype of object_type_1. Note -- that this function will return 'f' if object_type_1 = -- object_type_2 function is_subtype_p ( object_type_1 in acs_object_types.object_type%TYPE, object_type_2 in acs_object_types.object_type%TYPE ) return char; end acs_object_type; / show errors create or replace package acs_attribute is -- define an object attribute function create_attribute ( object_type in acs_attributes.object_type%TYPE, attribute_name in acs_attributes.attribute_name%TYPE, datatype in acs_attributes.datatype%TYPE, pretty_name in acs_attributes.pretty_name%TYPE, pretty_plural in acs_attributes.pretty_plural%TYPE default null, table_name in acs_attributes.table_name%TYPE default null, column_name in acs_attributes.column_name%TYPE default null, default_value in acs_attributes.default_value%TYPE default null, min_n_values in acs_attributes.min_n_values%TYPE default 1, max_n_values in acs_attributes.max_n_values%TYPE default 1, sort_order in acs_attributes.sort_order%TYPE default null, storage in acs_attributes.storage%TYPE default 'type_specific', static_p in acs_attributes.static_p%TYPE default 'f' ) return acs_attributes.attribute_id%TYPE; procedure drop_attribute ( object_type in varchar2, attribute_name in varchar2 ); procedure add_description ( object_type in acs_attribute_descriptions.object_type%TYPE, attribute_name in acs_attribute_descriptions.attribute_name%TYPE, description_key in acs_attribute_descriptions.description_key%TYPE, description in acs_attribute_descriptions.description%TYPE ); procedure drop_description ( object_type in acs_attribute_descriptions.object_type%TYPE, attribute_name in acs_attribute_descriptions.attribute_name%TYPE, description_key in acs_attribute_descriptions.description_key%TYPE ); end acs_attribute; / show errors create or replace package body acs_object_type is procedure create_type ( object_type in acs_object_types.object_type%TYPE, pretty_name in acs_object_types.pretty_name%TYPE, pretty_plural in acs_object_types.pretty_plural%TYPE, supertype in acs_object_types.supertype%TYPE default 'acs_object', table_name in acs_object_types.table_name%TYPE, id_column in acs_object_types.id_column%TYPE, package_name in acs_object_types.package_name%TYPE default null, abstract_p in acs_object_types.abstract_p%TYPE default 'f', type_extension_table in acs_object_types.type_extension_table%TYPE default null, name_method in acs_object_types.name_method%TYPE default null ) is v_package_name acs_object_types.package_name%TYPE; begin -- XXX This is a hack for losers who haven't created packages yet. if package_name is null then v_package_name := object_type; else v_package_name := package_name; end if; insert into acs_object_types (object_type, pretty_name, pretty_plural, supertype, table_name, id_column, abstract_p, type_extension_table, package_name, name_method) values (object_type, pretty_name, pretty_plural, supertype, table_name, id_column, abstract_p, type_extension_table, v_package_name, name_method); end create_type; procedure drop_type ( object_type in acs_object_types.object_type%TYPE, cascade_p in char default 'f' ) is cursor c_attributes (object_type IN varchar) is select attribute_name from acs_attributes where object_type = object_type; begin -- drop all the attributes associated with this type for row in c_attributes (drop_type.object_type) loop acs_attribute.drop_attribute ( drop_type.object_type, row.attribute_name ); end loop; delete from acs_attributes where object_type = drop_type.object_type; delete from acs_object_types where object_type = drop_type.object_type; end drop_type; function pretty_name ( object_type in acs_object_types.object_type%TYPE ) return acs_object_types.pretty_name%TYPE is v_pretty_name acs_object_types.pretty_name%TYPE; begin select t.pretty_name into v_pretty_name from acs_object_types t where t.object_type = pretty_name.object_type; return v_pretty_name; end pretty_name; function is_subtype_p ( object_type_1 in acs_object_types.object_type%TYPE, object_type_2 in acs_object_types.object_type%TYPE ) return char is v_result integer; begin select count(*) into v_result from dual where exists (select 1 from acs_object_types t where t.object_type = is_subtype_p.object_type_2 connect by prior t.object_type = t.supertype start with t.supertype = is_subtype_p.object_type_1); if v_result > 0 then return 't'; end if; return 'f'; end is_subtype_p; end acs_object_type; / show errors create or replace package body acs_attribute is function create_attribute ( object_type in acs_attributes.object_type%TYPE, attribute_name in acs_attributes.attribute_name%TYPE, datatype in acs_attributes.datatype%TYPE, pretty_name in acs_attributes.pretty_name%TYPE, pretty_plural in acs_attributes.pretty_plural%TYPE default null, table_name in acs_attributes.table_name%TYPE default null, column_name in acs_attributes.column_name%TYPE default null, default_value in acs_attributes.default_value%TYPE default null, min_n_values in acs_attributes.min_n_values%TYPE default 1, max_n_values in acs_attributes.max_n_values%TYPE default 1, sort_order in acs_attributes.sort_order%TYPE default null, storage in acs_attributes.storage%TYPE default 'type_specific', static_p in acs_attributes.static_p%TYPE default 'f' ) return acs_attributes.attribute_id%TYPE is v_sort_order acs_attributes.sort_order%TYPE; v_attribute_id acs_attributes.attribute_id%TYPE; begin if sort_order is null then select nvl(max(sort_order), 1) into v_sort_order from acs_attributes where object_type = create_attribute.object_type and attribute_name = create_attribute.attribute_name; else v_sort_order := sort_order; end if; select acs_attribute_id_seq.nextval into v_attribute_id from dual; insert into acs_attributes (attribute_id, object_type, table_name, column_name, attribute_name, pretty_name, pretty_plural, sort_order, datatype, default_value, min_n_values, max_n_values, storage, static_p) values (v_attribute_id, object_type, table_name, column_name, attribute_name, pretty_name, pretty_plural, v_sort_order, datatype, default_value, min_n_values, max_n_values, storage, static_p); return v_attribute_id; end create_attribute; procedure drop_attribute ( object_type in varchar2, attribute_name in varchar2 ) is begin -- first remove possible values for the enumeration delete from acs_enum_values where attribute_id in (select a.attribute_id from acs_attributes a where a.object_type = drop_attribute.object_type and a.attribute_name = drop_attribute.attribute_name); delete from acs_attributes where object_type = drop_attribute.object_type and attribute_name = drop_attribute.attribute_name; end drop_attribute; procedure add_description ( object_type in acs_attribute_descriptions.object_type%TYPE, attribute_name in acs_attribute_descriptions.attribute_name%TYPE, description_key in acs_attribute_descriptions.description_key%TYPE, description in acs_attribute_descriptions.description%TYPE ) is begin insert into acs_attribute_descriptions (object_type, attribute_name, description_key, description) values (add_description.object_type, add_description.attribute_name, add_description.description_key, add_description.description); end; procedure drop_description ( object_type in acs_attribute_descriptions.object_type%TYPE, attribute_name in acs_attribute_descriptions.attribute_name%TYPE, description_key in acs_attribute_descriptions.description_key%TYPE ) is begin delete from acs_attribute_descriptions where object_type = drop_description.object_type and attribute_name = drop_description.attribute_name and description_key = drop_description.description_key; end; end acs_attribute; / show errors