When someone filters on a timestamp field (ie a date field) and uses the offset to say something like 10 days ago (ie -10 day) in the filter's settings this breaks the time based caching.

The reason being that DBTNG's preExecute() function, in plugins/views_plugins_cache.inc, is converting ***CURRENT_TIME*** to it's timestamp value before the cache key is determined. Hence in lieu of the the ***CURRENT_TIME*** placeholder appearing in the build_info array the timestamp appears. The end result is the cache key is different every second and therefore the cached is only valid for 1 second. :(

timestamp in the SQL string used to compute the cache key in D7/Views3

node_revision.timestamp >= 1330976131-864000

timestamp in the SQL string used to compute the cache key in D6

node_revision.timestamp >= ***CURRENT_TIME*** - 864000

the code at issue here is line 264 for the plugins/views_plugins_cache.inc

259       foreach (array('query','count_query') as $index) {
260         // If the default query back-end is used generate SQL query strings from
261         // the query objects.
262         if ($build_info[$index] instanceof SelectQueryInterface) {
263           $query = clone $build_info[$index];
264           $query->preExecute();
265           $build_info[$index] = (string)$query;
266         }
267       }

I don't know the fix right off the top of my head, though I know for the time being we're gonna overwrite the handler with our own get_results_key(0 and get_output_key. Seems to me the fix is one of two things.

1.) Get ***CURRENT_TIME*** passed as a placeholder ala :db_condition_placeholder_x in build_info['query'] (and build_info['count_query']), which would have to happen in the views_handlers_filter_date handler
2.) Find a way to get the meta data form the SelectQuery objects

2 will be much more ugly than 1. :)

Comments

Title:offset timestamp breaks time based cache handlerViews failing to cache effectively when offsets are used in timestamp filters (D6 -> D7 regression)

No it's still the same issue

The easiest solution proposed to date is to use the Date filter which formats the SQL as:

(DATE_FORMAT(ADDTIME(FROM_UNIXTIME(node_revision.timestamp), SEC_TO_TIME(-18000))

I'm assuming we can change the data handler to follow this pattern, but hasn't looked yet.

One of the problems with changing the date filter to the proposed sql is that there are performance issues with running functions against fields in the where clause. this forces a table scan because the logic has to be applied to every row in the table. The better bet is going to be to use the mysql specific function: "unix_timestamp()" rather than php's request date.

luckily the node_revision.timestamp field is still using ***current_time*** see:

<?php
 
/**** views/handlers/views_handler_filter_date.inc  @ line 141***/
 
function op_simple($field) {
   
$value = intval(strtotime($this->value['value'], 0));
    if (!empty(
$this->value['type']) && $this->value['type'] == 'offset') {
     
$value = '***CURRENT_TIME***' . sprintf('%+d', $value); // keep sign
   
}
   
// This is safe because we are manually scrubbing the value.
    // It is necessary to do it this way because $value is a formula when using an offset.
   
$this->query->add_where_expression($this->options['group'], "$field $this->operator $value");
  }
?>

the problem is that the cache key is being generated after the tokens in the sql are replaced:

<?php
/* views/plugins/views_plugin_cache.inc @ line 259 */
       
if ($build_info[$index] instanceof SelectQueryInterface) {
         
$query = clone $build_info[$index];
         
$query->preExecute();
         
$build_info[$index] = (string)$query;
        }
?>

this has to be done this way because modules like organic groups use tokens like "***current_group***". if the query was cached before tokenization then every group would see the same information, but the revision time would work.. so its a catch 22.

you could probably get away with changing the value that the token ***current_time*** uses by declaring a better value (such as unix_timestamp() ) in a custom module that implements hook_views_query_substitutions()

Hope this helps!

We couldn't get hook_views_query_substituions() working as it seems on only want you to add placeholders not replace current ones.

The following fixes this issue:

/**
* Implements hook_views_query_alter().
*/
function <module_name>_views_query_alter(&$view, &$query) {
  // Replace the ***CURRENT_TIME*** placeholder with unix_timestamp()
  // Note: This function is MYSQL compliant only, it will fail in Postgres, SQLlite, Oracle, SQL
  // Server etc...
  // see http://drupal.org/node/1469188 to learn more about the reasoning
  foreach ($query->where as $where_count => $where) {
    if (count($where['conditions'])) {
      foreach($where['conditions'] as $key => $condition) {
        if ( is_array($condition) && isset($condition['field']) && is_string($condition['field']) && substr_count($condition['field'], '***CURRENT_TIME**')) {
          $query->where[$where_count]['conditions'][$key]['field'] = strtr($condition['field'],array('***CURRENT_TIME***' => 'unix_timestamp()'));
        }
      }
    }
  }
}

@bigjim,
does #1055616: Query arguments should be replaced before generating cache ID work for you? It is the follow-up from #1469950: "Query results" caching does not respect changed values of exposed filters, but is still evolving.
[EDIT] I tested it, it doesn't.