May 2009 - Development - lists.drupal.org

Proposed Apocrypha
by Jeff Eaton 07 May '09

07 May '09

Crell's Law: If an API must be use-case-optimized, make it swappable & tailor the default for cheap shared hosting. High-end sites can swap. Eaton's Corollary: If an API is swappable, write two implementations. APIs with one test case are rarely flexible enough for the second. --eaton

11 13

Re: [development] Database / SQL future thoughts
by Chris Johnson 07 May '09

07 May '09

Perhaps before this discussion gets too far astray -- or maybe such digression is impossible to avoid! :-) My point in posting this was to elicit folks who were interested in the database usage and performance for the core parts of Drupal, and in particular the folks who I through the past years have observed as being especially astute and involved (and if I left your name off that short list, it's only because I forgot your name or other such failure on my part -- no slight or insult intended). I was particularly hopeful that folks would read the comments, and take to heart those written in favor of SQL, such as those by Robert Young. I didn't want to bias the conversation by injecting my opinion too early, but I'm in the camp that says things like BigTable are really just reinventions of older technology, AND that the death of RDBMS/SQL is not nearly as soon as some might think. For Drupal, I think it may make sense to attempt to make the SQL as simple as possible, avoiding the really complex capabilities and doing more of that work in PHP, where most of the developers actually have some expertise. This is especially true since MySQL's MyISAM table engine is really poor at doing anything beyond that. If we were to move to using MVCC[1] engines like Postgres, Oracle and MySQL with InnoDB or Falcon, then more complex SQL would be useful. Unfortunately, most Drupal developers don't have the SQL skills needed, and even worse, most people are not going to have the ability to physically optimize the database for performance (i.e. skilled DBA person, access to MySQL settings at most hosting services, etc.). Hence, the former course of using only the simplest, most primitive SQL statements appeals to me for Drupal. It's that last point I'd really like to have criticized. Is it possible to do that? Especially in light of DBTNG, where is the line between simple statements and complex statements? Lastly, although many Drupal-based sites are database limited, many are PHP-code interpretation (# of files/lines parsed) or bandwidth (fast JS/image pages) limited, too. My goal is simple: make my hundred module websites respond in less than 2 seconds! :-D Thanks for participating in this discussion, no matter which tangent you're on. ..chris [1] http://en.wikipedia.org/wiki/Multiversion_concurrency_control

6 6

Database / SQL future thoughts
by Chris Johnson 06 May '09

06 May '09

Folks who care about the direction and performance of the Drupal database (and developers just generally interested in database backends for applications) should read this blog posting by Bob Cringley -- and more importantly, the comments written by some folks who know way more about databases than Mr. Cringely: http://www.cringely.com/2009/05/the-sequel-dilemma/ David Strauss and Larry Garfield, as our two current DB experts (IMHO, of course) -- I'd especially like you to digest the more pertinent comments and think about how we can simplify our database access, and hence optimize our performance. I'm about to go off an research Hadoop a bit, but my gut feeling is the comments which say SSD and proper, simple use of SQL and good data paths will be the right answer for the next decade or so are probably on the right mark. ..chris

18 35

hook_user('categories')
by David Cohen 06 May '09

06 May '09

Sometime in the 5.x-6.x timeframe, the API for hook_user($op == 'categories') changed in a major way. No longer is the $account parameter passed in, and I think the data structure to be returned gained a lot of options. But I can't find the documentation for this. Its not in the 5.x to 6.x page on d.o (http://drupal.org/node/114774) nor is it reflected on http://api.drupal.org/api/function/hook_user/6. Can someone point me to general doc, or an example of how to emulate the following logic in D6. The logic is basically to show the user an edit category only if they have permission to change their own settings. if ($op == 'categories') { if (user_access('edit own extended permissions') && $user->uid == $account->uid) { // build the data structure } } The above logic wont apply in D6 because $account is not passed in, and the return value is expected to have new menu data structure elements which take the place of that logic. But I'm struggle to figure out, in part because I can't find the doc. thanks.

4 4

views: chaining tables
by Lluís 05 May '09

05 May '09

I am have a node view which should show data from a 3rd table: node->vid relates to node_cc_proveidors->vid node_cc_assentaments->provedir_nid relates to node_cc_proveidors->nid So starting from {node} I should get node_cc_assentaments->valor ; in SQL what I want is similar to: SELECT title, valor FROM cc2_node node LEFT JOIN cc2_node_cc_proveidors node_cc_proveidors ON node_cc_proveidors.vid = node.vid LEFT JOIN cc2_node_cc_assentaments node_cc_assentaments ON node_cc_assentaments.proveidor_nid = node_cc_proveidors.nid WHERE type IN ('proveidor') Any hint? thanks Right now my view looks like this. <?php /** * Implementation of hook_views_data() */ function cc_proveidors_views_data() { $data['node_cc_proveidors']['table']['group'] = 'ComptaCAU Proveïdors'; //trans $data['node_cc_proveidors']['table']['join'] = array( 'node' => array( 'left_field' => 'vid', 'left_table' => 'node', 'field' => 'vid', ), 'cc_proviedors_assentaments' => array( //alias for {node_cc_assentaments} 'left_table' => 'node_cc_assentaments', 'left_field' => 'proveidor_nid', 'table' => 'node_cc_assentaments', 'field' => 'nid', ) ); $data['node_cc_proveidors']['nif'] = array( 'title' => 'Nif del proveïdor', //trans 'help' => '.', //trans 'field' => array( 'field' => 'nif', 'handler' => 'views_handler_field', 'click sortable' => TRUE, ), 'filter' => array( 'handler' => 'views_handler_filter_string', ), 'argument' => array( 'handler' => 'views_handler_argument_string', ), 'sort' => array( 'handler' => 'views_handler_sort', ), ); $data['cc_proviedors_assentaments']['table']['group'] = 'ComptaCAU Proveïdors 2'; //trans $data['cc_proviedors_assentaments']['table']['join'] = array( 'node_cc_proveidors' => array( 'left_table' => 'node_cc_assentaments', 'left_field' => 'nid', 'field' => 'proveidor_nid', 'table' => 'cc_assentaments', ), ); $data['cc_proviedors_assentaments']['nid'] = array( 'title' => 'Diners gastats al proveidor', //trans 'help' => 'Llista totes les despeses del proveïdor, permetent agrupar-les i fer totals.', //trans 'field' => array( 'real field' => 'valor', 'handler' => 'views_handler_field', 'click sortable' => TRUE, ), ); return $data; } -- *La vida és com una taronja, què esperes a exprimir-la? *Si creus que l'educació és cara, prova la ignorància. *La vida és com una moneda, la pots gastar en el que vulguis però només una vegada. *Abans d'imprimir aquest missatge, pensa en el medi ambient.

1 0

{variable} entry format
by Eric Schaefer 04 May '09

04 May '09

Hi List, I was always wondering about the format of the value column in the {variable} table (e.g. s:7:"garland";) Why the length of the string? Some kind of optimization? Regards, Eric

3 3

views2: how to add "link to node" in custom filed
by Lluís 04 May '09

04 May '09

I have created a custom node and now I am addint "views support" to it. I have a custom field which should be a link to the full node; I added: $data['node_cc_projects']['long_name'] = array( 'title' => "long name", //trans 'help' => 'long name of the node.', //trans 'field' => array( 'field' => 'long_name', 'handler' => 'views_handler_field_node', 'click sortable' => TRUE, ), 'sort' => array( 'handler' => 'views_handler_sort', ), 'filter' => array( 'handler' => 'views_handler_filter_string', ), ); but the link created is "?q=node/" without the node number. What am I missing? thanks -- *La vida és com una taronja, què esperes a exprimir-la? *Si creus que l'educació és cara, prova la ignorància. *La vida és com una moneda, la pots gastar en el que vulguis però només una vegada. *Abans d'imprimir aquest missatge, pensa en el medi ambient.

3 4

Custom module, do you think I should add it to cvs.drupal.org ?
by Pierre Rineau 03 May '09

03 May '09

Hi folks, I made a really, really simple module (3 lines and a JS file). It uses the "title" HTML attribute on text and textarea HTML inputs to display an empty value in the input, which disappear on focus, and re-appear on focus out if input is still empty. This is simple, I saw something like 10 or 20 different JS implementations; I choosed one of them, (one I saw on Drupal.org's forums), adapted it a bit the JS file to be more coherent with Drupal6. The real module just does a "drupal_add_js()" in hook_init() (which should be compatible with aggressive caching). Do you think this is a good idea to commit it in the Drupal CVS, as a new project? Or do you known some modules which already does the same thing, in a better way? Regards, Pierre.

5 8