Previously on the blog
RSS feed
  1. Using POG with Flex
  2. Optimizing your web application
  3. Regenerating large objects
  4. PHP4 or PHP5
  5. New and Improved
  6. Evolution of a cube
  7. POG Museum
  8. POG 3.0 alpha
  9. Initial Performance results Part 2
  10. Initial performance results
  11. Proposal: POG 3.0 object model
  12. Suggest a feature
  13. A new year, A new POG release
  14. Many-Many relations
  15. POG 2.5 Released
  16. POG 2.5 beta
  17. Automatic table alignment
  18. New version: 2.1.2 released
  19. RSS should work well now
  20. RSS feed glitches
  21. What's new in 2.1.0
  22. PHP Objects 2.1.0 (preview)
  23. PHP Object relations FAQ
  24. PHP Object Relations
  25. Searching base64 encoded text
  26. How to debug POG-generated objects
  27. POG UI Tips
  28. Featuring Of Interest links
  29. PHP CRUD
  30. POG 2.0.1: A better code generator
  31. A look at the POG SOAP API
  32. POG 2.0.0 released
  33. Coming soon: Generate parent-child objects
  34. Generated abstraction v/s dynamic abstraction
  35. Zend Framework preview
  36. Coming soon: Generate Objects through SOAP
  37. Easily save images and files to a database
  38. PHP, Paypal & POG
  39. Five advanced Code Generator tips
  40. PHP Pagination using generated objects
  41. PHP Code Generator benchmarks
  42. Representing database objects using an AJAX Tree interface
  43. Using SETUP in a production environment
  44. Description of the generated object package
  45. Introducing PHP Object Generator version 1.6
  46. Using AJAX and PHP Object Generator
  47. When to use Object->SaveNew()
  48. Generating PHP objects in 2006
  49. Happy Holidays
  50. A short video of the POG Setup process
  51. A sneak peek at POG 1.6
  52. POG Tip: Field limits
  53. Previous versions.
  54. Searching the blog and tutorials sections
  55. Generating code with "Other" SQL data types
  56. Five general POG tips
  57. POG source code locations
  58. Microsoft SQL 2005 Express Edition
  59. Impatiently awaiting PHP 5.1 and PDO
  60. Php Object Generator goes open source
  61. POG generates PDO compatible code
  62. Oracle to offer free database
  63. POG Google group
  64. Database Wrappers and POG
  65. Revisions
  66. The generator blog
  67. An explanation of the 'Escape' function.
  68. Mirror, mirror
  69. Using POG to solve real world problems
  70. A php object-relational database tool
  71. A simple and flexible Object Oriented approach to PHP

Want more Php Object Generator?
Back to the Code Generator
The POG Google group
The POG tutorials/code samples
The POG mirror site

Many-Many relations

written 4608 days ago

Since POG 1.0 was launched about a year ago now, there has been numerous requests for object relations. POG 2.0 addressed the issues of parent-child (1-many, many-1) relations. Still, more work needed to be done for POG to really be useful in situations where many-many relations were needed. POG 2.5, released about a week ago, finally provides a simple, yet, powerful solution: Sibling Relations.

In the POG world, a sibling is an object that relates to one or many other sibling objects. Real world examples include the relations between Magazine and Subscribers: A subscriber can subscribe to one or more different magazines.

The object methods generated by POG to abstract many-many relations are similar to the ones generated for parent – child relations. We kept the API consistent so that the objects remain intuitive, and yet, are more powerful. The programmer can almost forget the underlying relations.

For instance, let’s say we have a Magazine and Subscriber object which are siblings. To associate a Magazine to a Subscriber, we only need to do something like this:


The thing to note here is that if Subscriber and Magazine were parent and child, instead of siblings, the code would still be


On the database level, however, the way the data is stored by POG is quite different. In the case of a parent-child relation, the child simply refers to the parentId using a column in the child table. In the case of siblings, POG generates a mapping (join) table which stores the sibling1_id and sibling2_id of related sibling. The data is inserted, retrieved and deleted from this mapping table transparently and does not have to be accessed directly by the developer.

More info on sibling relations can be found in the POG relations PDF document

We hope that the introduction of sibling relations will help accelerate your development even more.

  Textile Help
About Php Object Generator
This is a weblog about the Php Object Generator (POG) project, OO PHP, databases and Php code generators in general.

Php Object Generator, (POG) is an open source PHP code generator which automatically generates clean & tested Object Oriented code for your PHP4/PHP5 application.

Subscribe to our RSS feed

Feedback, Feature Requests, Bugs to:
The POG Google group

Send us a Hello through email