Building Class Hierarchies

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Author	Message
Tristan Koen	Thursday 12 June 2003 6:50:04 am Hi All, Is it possible to build class hierarchies in ezPublish? If I create two classes, A and B, I want to build them so that instances of B can only have an instance of A as a parent. Very much like a foreign key relationship in an RDBMS. I could simulate this behaviour using related objects, but I cannot enforce the relationship which doesn't help.
Bruce Morrison	Thursday 12 June 2003 4:28:46 pm You can do this using permissions. Configure the system so that you can only create a class B for parents of class A. Class A acts like a "folder" having child content of class B. Cheers Bruce designIT My Blog: http://www.stuffandcontent.com/ Follow me on twitter: http://twitter.com/brucemorrison Consolidated eZ Publish Feed : http://friendfeed.com/rooms/ez-publish
Tristan Koen	Friday 13 June 2003 1:22:55 am Hi Bruce. Thanks for the answer, but you have really confused me. Where you say "Class A acts like a "folder" having child content of class B", that is exactly what I want, but I don't understand your reasoning. My understanding is as follows: 1. Create class A and class B. Class B will have a "related object" attribute that will be used to make the link to A. 2. In the admin interface, create a new role called ABhierarchy for arguments' sake. 3. The role would make the following restriction: - Module: content (you can't do all of them which makes me wonder why there is an 'All' option in the first place). - Function: create - Class: B - Section: Any - Parent Class: A 4. Apply this role to all of your users? The problem with this approach is that the restriction is placed on the user, not on the data itself. I realise that the two are somewhat equivalent from a practical point of view, but it is possible that a mis-configured user could make a big mess. If you mean something else, please explain. I am getting horribly stuck here. I would also like to have a data structure where an arbitrary number of objects of Class B can be created as children of object A. Thanks Tristan

Author

Message

Thursday 12 June 2003 6:50:04 am

Hi All,

Is it possible to build class hierarchies in ezPublish? If I create two classes, A and B, I want to build them so that instances of B can only have an instance of A as a parent. Very much like a foreign key relationship in an RDBMS.
I could simulate this behaviour using related objects, but I cannot enforce the relationship which doesn't help.

Bruce Morrison

Thursday 12 June 2003 4:28:46 pm

You can do this using permissions. Configure the system so that you can only create a class B for parents of class A.

Class A acts like a "folder" having child content of class B.

Cheers
Bruce
designIT

My Blog: http://www.stuffandcontent.com/
Follow me on twitter: http://twitter.com/brucemorrison
Consolidated eZ Publish Feed : http://friendfeed.com/rooms/ez-publish

Tristan Koen

Friday 13 June 2003 1:22:55 am

Hi Bruce.

Thanks for the answer, but you have really confused me. Where you say "Class A acts like a "folder" having child content of class B", that is exactly what I want, but I don't understand your reasoning.

My understanding is as follows:
1. Create class A and class B. Class B will have a "related object" attribute that will be used to make the link to A.
2. In the admin interface, create a new role called ABhierarchy for arguments' sake.
3. The role would make the following restriction:
- Module: content (you can't do all of them which makes me wonder why there is an 'All' option in the first place).
- Function: create
- Class: B
- Section: Any
- Parent Class: A
4. Apply this role to all of your users?

The problem with this approach is that the restriction is placed on the user, not on the data itself. I realise that the two are somewhat equivalent from a practical point of view, but it is possible that a mis-configured user could make a big mess. If you mean something else, please explain. I am getting horribly stuck here.

I would also like to have a data structure where an arbitrary number of objects of Class B can be created as children of object A.

Thanks

Tristan

eZ debug

Timing:	Jan 18 2025 17:42:31
Script start
Timing:	Jan 18 2025 17:42:31
Module start 'layout'
Timing:	Jan 18 2025 17:42:31
Module start 'content'
Timing:	Jan 18 2025 17:42:33
Module end 'content'
Timing:	Jan 18 2025 17:42:33
Script end

Main resources:

Total runtime	1.0962 sec
Peak memory usage	4,096.0000 KB
Database Queries	57

Timing points:

Checkpoint	Start (sec)	Duration (sec)	Memory at start (KB)	Memory used (KB)
Script start	0.0000	0.0062	587.9141	152.6250
Module start 'layout'	0.0062	0.0033	740.5391	39.4453
Module start 'content'	0.0096	1.0851	779.9844	534.1328
Module end 'content'	1.0947	0.0014	1,314.1172	12.1641
Script end	1.0961		1,326.2813

Time accumulators:

Accumulator	Duration (sec)	Duration (%)	Count	Average (sec)
Ini load
Load cache	0.0041	0.3776	16	0.0003
Check MTime	0.0014	0.1263	16	0.0001
Mysql Total
Database connection	0.0007	0.0625	1	0.0007
Mysqli_queries	1.0430	95.1537	57	0.0183
Looping result	0.0006	0.0537	55	0.0000
Template Total	1.0512	95.9	2	0.5256
Template load	0.0018	0.1616	2	0.0009
Template processing	1.0494	95.7334	2	0.5247
Template load and register function	0.0002	0.0192	1	0.0002
states
state_id_array	0.0084	0.7704	1	0.0084
state_identifier_array	0.0012	0.1117	2	0.0006
Override
Cache load	0.0014	0.1313	30	0.0000
Sytem overhead
Fetch class attribute can translate value	0.0005	0.0447	2	0.0002
Fetch class attribute name	0.0011	0.0989	4	0.0003
XML
Image XML parsing	0.0007	0.0635	2	0.0003
class_abstraction
Instantiating content class attribute	0.0000	0.0007	4	0.0000
General
dbfile	0.0011	0.0996	16	0.0001
String conversion	0.0000	0.0007	4	0.0000
Note: percentages do not add up to 100% because some accumulators overlap

Templates used to render the page:

Usage	Requested template	Template	Template loaded
1	node/view/full.tpl	full/forum_topic.tpl	extension/sevenx/design/simple/override/templates/full/forum_topic.tpl
3	content/datatype/view/ezxmltext.tpl	<No override>	extension/community_design/design/suncana/templates/content/datatype/view/ezxmltext.tpl
6	content/datatype/view/ezxmltags/paragraph.tpl	<No override>	extension/ezwebin/design/ezwebin/templates/content/datatype/view/ezxmltags/paragraph.tpl
3	content/datatype/view/ezxmltags/line.tpl	<No override>	design/standard/templates/content/datatype/view/ezxmltags/line.tpl
1	content/datatype/view/ezimage.tpl	<No override>	extension/sevenx/design/simple/templates/content/datatype/view/ezimage.tpl
1	print_pagelayout.tpl	<No override>	extension/community/design/community/templates/print_pagelayout.tpl
Number of times templates used: 15 Number of unique templates used: 6

Time used to render debug report: 0.0001 secs