This document summarizes some of the key differences in Drupal 7 development compared to earlier versions, including changes to hook implementations, the introduction of a registry database, an object-oriented approach to database queries, and recommendations for best practices when working with Drupal 7.

1. Drupal 7 development: first impressions Dennis Povshedny, madcap.nl

2. Minor stuff Like different *.info files format (dependencies[])

3. API somewhere changed As well as for D5 to D6 migration Versions 4.6 hook_form(&$node, &$param) 4.7 hook_form(&$node) 5 hook_form(&$node, $form_values) 6 hook_form(&$node, $form_state) 7 hook_form($node, $form_state)

4. Registry introduced Two tables in DB to hold all registered functions kind of OOP based on procedural platform Rebuild registry regularly with clearing cache, like: - call drupal_flush_all_caches() - truncate all cache_* tables

5. DB is now object oriented, baby! No more good old db_query; Use PDO (PHP Data Objects) instead; Looks like a hell at a first sight

6. D6 way $entry = db_query('SELECT parent_nid FROM {ts_activity_hierarchy} WHERE ts_activity_hierarchy.nid = ' . $nid);

7. D7 way $query = db_select('ts_activity_hierarchy'); $query->addField('ts_activity_hierarchy', 'parent_nid' ); $query->condition('ts_activity_hierarchy.nid', $nid); $result = $query->execute(); $entry = db_fetch_object($result);

8. Translate, please! $num_revoked = db_delete('ts_activity_users') ->condition('activity_nid', $nid) ->condition('uid', $userid, 'IN') ->execute(); db_query('DELETE FROM {ts_activity_users} WHERE activity_nid=' . $nid . ' AND uid IN (' . implode(',', $userid) . ')');

9. DB: guard pattern { $guard = db_transaction(); ... }

10. Beautiful doc for deal with DB hell http://drupal.kollm.org/doxygen/drupal-phpdoc/class_select_query.html

12. How stable is UNSTABLE? Now we use UNSTABLE 9 even node_ tables has changed recently Shall I start or wait?

13. Other good practices Write Doxygen - style comments; Enjoy pure PHP5 cause PHP4 is no longer supported – feel free to use 'clone', etc ...

14. Thank you! Questions and ideas – welcome! Drupal 7 – just try it! :)