Index: openacs-4/packages/acs-content-repository/www/doc/guide/object-relationships.html
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-content-repository/www/doc/guide/object-relationships.html,v
diff -u -r1.1.1.1 -r1.1.1.1.30.1
--- openacs-4/packages/acs-content-repository/www/doc/guide/object-relationships.html 13 Mar 2001 22:59:26 -0000 1.1.1.1
+++ openacs-4/packages/acs-content-repository/www/doc/guide/object-relationships.html 22 Jun 2016 07:40:41 -0000 1.1.1.1.30.1
@@ -4,7 +4,7 @@
Object Relationships
- Content Repository : Developer Guide
+ Content Repository : Developer Guide
Many applications of the content repository require that content
@@ -36,7 +36,7 @@
an associated photo are one example of this. These "parent-child"
relationships are handled by the basic hierarchical organization of the
content repository. Every item has a parent item, represented internally
-by the parent_id column in the cr_items table.
+by the parent_id column in the cr_items table.
It is often desirable to constrain the number and content type of
child items. For example, the specifications for a news story may
@@ -47,33 +47,33 @@
presented to the user. The layout for a photo album may have a special
position for a "featured" photo.
-
+
The content repository accomodates these situations in the
following ways:
-- An API procedure, content_type.register_child_type, may be
+
- An API procedure, content_type.register_child_type, may be
used to specify the minimum and maximum number of children of a
particular content type that an item may have. You may optionally
specify a "tag" for identifying child items of the same type. For
example, you may want to allow only 1 image with the "featured" tag,
and up to 8 other images without this.
-
- A Boolean API function, content_item.is_valid_child,
+
- A Boolean API function, content_item.is_valid_child,
which checks all registered child constraints on the content type of
an item and returns true if it is currently possible to add an child
of a particular type to tan item. Note that this function does not
protect against concurrent transactions; it is only foolproof if you
-lock the cr_child_rels table beforehand.
+lock the cr_child_rels table beforehand.
-
- A mapping table, cr_child_rels, which contains two
-attributes, order_n and relation_tag, that may be
+
- A mapping table, cr_child_rels, which contains two
+attributes, order_n and relation_tag, that may be
used to characterize the parent-child relationship. Parent-child
relationships are themselves treated as ACS Objects, so this table may
be extended with additional attributes as required by the
@@ -82,7 +82,7 @@
Note that there is no currently no explicit API to "add a child."
You specify the parent of an item upon creating it. You can use the
-API procedure content_item.move to change the parent of an
+API procedure content_item.move to change the parent of an
item.
Item-Object Relationships
@@ -99,24 +99,24 @@
is provided for parent-child relationships:
-- An API procedure, content_type.register_relation_type,
+
- An API procedure, content_type.register_relation_type,
may be used to specify the minimum and maximum number of relations
with a particular object type that an item may have. There is no
limitation on the type of objects that may be related to content
items. If you wish to relate content items to other content items,
however, the object type should specify a content type (a subtype of
-content_revision) rather than simply content_item.
+content_revision) rather than simply content_item.
As for parent-child relationship constraints, ou may optionally
specify a "tag" for identifying related objects of the same type.
-
- A Boolean API function, content_item.is_valid_relation,
+
- A Boolean API function, content_item.is_valid_relation,
which checks all registered constraints on the content type of an item
and returns true if it is currently possible to relate an object of a
particular type to an item.
-
- A mapping table, cr_item_rels, which contains two
-attributes, order_n and relation_tag, that may be
+
- A mapping table, cr_item_rels, which contains two
+attributes, order_n and relation_tag, that may be
used to characterize the item-object relationship. Item-object
relationships are themselves treated as ACS Objects, so this table may
be extended with additional attributes as required by the
@@ -133,7 +133,7 @@
karlg@arsdigita.com
-Last modified: $Id$
+Last modified: $Id$