diff options
Diffstat (limited to 'engine/lib/database.php')
| -rw-r--r-- | engine/lib/database.php | 39 |
1 files changed, 20 insertions, 19 deletions
diff --git a/engine/lib/database.php b/engine/lib/database.php index b41eb4cda..a7949788d 100644 --- a/engine/lib/database.php +++ b/engine/lib/database.php @@ -12,18 +12,19 @@ /** * Query cache for all queries. * - * Each query and its results are stored in this array as: + * Each query and its results are stored in this cache as: * <code> - * $DB_QUERY_CACHE[$query] => array(result1, result2, ... resultN) + * $DB_QUERY_CACHE[query hash] => array(result1, result2, ... resultN) * </code> + * @see elgg_query_runner() for details on the hash. * - * @warning be array this var may be an array or ElggStaticVariableCache depending on when called :( + * @warning Elgg used to set this as an empty array to turn off the cache * - * @global ElggStaticVariableCache|array $DB_QUERY_CACHE + * @global ElggLRUCache|null $DB_QUERY_CACHE * @access private */ global $DB_QUERY_CACHE; -$DB_QUERY_CACHE = array(); +$DB_QUERY_CACHE = null; /** * Queries to be executed upon shutdown. @@ -127,9 +128,8 @@ function establish_db_link($dblinkname = "readwrite") { // Set up cache if global not initialized and query cache not turned off if ((!$DB_QUERY_CACHE) && (!$db_cache_off)) { - // @todo everywhere else this is assigned to array(), making it dangerous to call - // object methods on this. We should consider making this an plain array - $DB_QUERY_CACHE = new ElggStaticVariableCache('db_query_cache'); + // @todo if we keep this cache in 1.9, expose the size as a config parameter + $DB_QUERY_CACHE = new ElggLRUCache(200); } } @@ -399,16 +399,14 @@ function elgg_query_runner($query, $callback = null, $single = false) { // Since we want to cache results of running the callback, we need to // need to namespace the query with the callback and single result request. - // http://trac.elgg.org/ticket/4049 + // https://github.com/elgg/elgg/issues/4049 $hash = (string)$callback . (int)$single . $query; // Is cached? if ($DB_QUERY_CACHE) { - $cached_query = $DB_QUERY_CACHE[$hash]; - - if ($cached_query !== FALSE) { + if (isset($DB_QUERY_CACHE[$hash])) { elgg_log("DB query $query results returned from cache (hash: $hash)", 'NOTICE'); - return $cached_query; + return $DB_QUERY_CACHE[$hash]; } } @@ -475,7 +473,7 @@ function insert_data($query) { } /** - * Update a row in the database. + * Update the database. * * @note Altering the DB invalidates all queries in {@link $DB_QUERY_CACHE}. * @@ -500,7 +498,7 @@ function update_data($query) { } /** - * Remove a row from the database. + * Remove data from the database. * * @note Altering the DB invalidates all queries in {@link $DB_QUERY_CACHE}. * @@ -526,15 +524,18 @@ function delete_data($query) { /** * Invalidate the query cache - * + * * @access private */ function _elgg_invalidate_query_cache() { global $DB_QUERY_CACHE; - if ($DB_QUERY_CACHE) { - /* @var ElggStaticVariableCache $DB_QUERY_CACHE */ + if ($DB_QUERY_CACHE instanceof ElggLRUCache) { $DB_QUERY_CACHE->clear(); elgg_log("Query cache invalidated", 'NOTICE'); + } elseif ($DB_QUERY_CACHE) { + // In case someone sets the cache to an array and primes it with data + $DB_QUERY_CACHE = array(); + elgg_log("Query cache invalidated", 'NOTICE'); } } @@ -667,7 +668,7 @@ function run_sql_script($scriptlocation) { /** * Format a query string for logging - * + * * @param string $query Query string * @return string * @access private |