1. Andrew Bacon ‟13
Carleton College

2. me:

3. me:

4. me:

5. at WSG:

6. ➡ entities
➡ relationships

7. entities:
stuff.

8. entities:
stuff like...
➡ sites ➡ news posts
➡ pages ➡ images, ...
➡ a cat

9. entities:
aggregations of
properties...
➡ id ➡ name
➡ type ➡ created_on, ...

10. entities:
some properties only
make sense for
certain types

11. entities:
some properties only make sense for certain
types, e. g.:
lol_cat boromir
breed

12. entities:
aggregations of
properties across
database tables.
➡ entity
➡ meta
➡ chunk
➡ newstype, image, ...

13. Some examples.
meta
➡ description
➡ keywords
chunk
➡ content
➡ author
image
➡ dimension
➡ image_type
newstype
➡ subtitle
➡ on_front_page

14. Some examples.
meta
➡ description
➡ keywords
chunk
➡ content
➡ author
image
➡ dimension
➡ image_type
newstype
➡ subtitle
➡ on_front_page
news post

15. Some examples.
meta
➡ description
➡ keywords
chunk
➡ content
➡ author
image
➡ dimension
➡ image_type
newstype
➡ subtitle
➡ on_front_page
image

16. not entities:
relationships

17. relationships
Things are related to other
things.
➡ entity_a and entity_b

18. relationships
silly examples:
nation_to_cat_monarch

19. relationships
silly examples:
lolrus_to_bukkit

20. relationships
real examples:
minisite_page_to_av
av_to_av_file
minisite_page_to_image
news_to_image

21. relationships
Things are related to other
things.
➡ directional
➡ entity_a and entity_b

22. detour:
relationships have direction.
➡ unidirectional
minisite_page_to_image

23. detour:
relationships have direction.
nation_to_cat_monarch

24. (disembodied)

25. detour:
relationships have direction.
➡ unidirectional
➡ bidirectional
site_to_user

26. detour:
real examples of directionality
➡ news_to_image

27. detour:
relationships have direction.
focus
related
news_post_to_...

28. detour:
relationships have direction.
image_to_... or ..._to_image
focus
related

29. relationships
Things are related to other
things.
➡ directional
➡ number-sensitive
➡ entity_a and entity_b

30. relationships
silly examples:
nation_to_cat_monarch

31. relationships
silly examples:
mom_to_kittens

32. relationships
real examples:
➡ news_to_image

33. relationships
Things are related to other
things.
➡ directional
➡ number-sensitive
➡ entity_a and entity_b
➡ pretty darn arbitrary

34. entities:
stuff like...
➡ sites ➡ news posts
➡ pages ➡ images, ...
➡ types?
➡ DB tables?!
➡ „type‟!?!?

35. putting it together
type_to_table relationships for
entity 3, “Site.”
rel_id entity_a entity_b rel_type
7 Site (3) site (8) 1
11628 Site (3) meta (82) 1
94766 Site (3)
ldap_cache
(37716)
1

36. entities in PHP
➡ objects of class Entity
➡ linked to corresponding entity
in DB (if exists)

37. entities in PHP
methods to know about
get_value($name, $value);
set_value($name);
id();

38. getting entities
entity constructor
entity selectors

39. the constructor
$e = new Entity($id);

40. the selector
$es =
new Entity_Selector($site);

41. selector
why I was afraid
➡ no formal introduction

42. selector
common tasks
What properties of entities can we select
based on?
➡ Type
➡ Relationship to a specific entity
➡ Has a property with a specific value
➡ ...?

43. selector
add_type($id);
Will select only entities of the given type.
$es->add_type(id_of(„image‟));

44. selector
add_relation($where);
Selects only entities where a specific
property meets some condition.
$es->add_relation(
„status.status != “pending”‟
);

45. selector
add_left_relationship($id[, $rel_id]);
selected entities must exist on the left side
of a relationship with $entity_id on the right
side. Optional $relationship_id.
“get the parent of the
given entity.”

46. selector
add_right_relationship($id[, $rel_id])
selected entities must exist on the right side
of a relationship with $entity_id on the left
side. Optional $relationship_id.
“get the child of the given
entity.”

47. selector
set_env(
„site‟, $site_id
);
always set this.
not the same thing as the site id you set in
the $es constructor.

48. selector
run_one([$type, $status, $error]);
Run the darn thing!
Returns an array of entities.

49. selector
an example:
Select all media works from a site
➡$es = new Entity_Selector($site);
➡$es->add_type(id_of(„av‟));
➡$result = $es->run_one()

50. selector
another example:
Select all images related to a news item (for
this site!)
➡$es = new Entity_Selector($site);
➡$es->add_type(id_of(„image‟));
➡$es->add_right_relationship(
$news_id,
relationship[_id_of(„news_to_image‟)
);
➡$result = $es->run_one()

51. selector
add_left_relationship_field(
$rel_name, $table, $field
);
If there are entities that are on the left side
of the given relationship, add the given
field.

52. selector
how to look up info about a type
Master admin -> types

54. more?!
you know enough now.

55. other thoughts
that guy sitting next to you is
AMAZING with $es.
➡ bigger selectors are not better.
➡ limit_tables, limit_fields
➡ fifth parameter of add_left_rel_field
➡ google group: reason-cms

56. goodies!!!!
available at
go.carleton.edu/...
slides! cheat sheet!
!?!?