cvs: php4 /pear/Cache/Container db.php

chregu Fri May 4 01:14:21 2001 EDT Modified files: /php4/pear/Cache/Container db.php Log: added low/higwater garbage collection to the db-container. dbx should follow soon Index: php4/pear/Cache/Container/db.php diff -u php4/pear/Cache/Container/db.php:1.11 php4/pear/Cache/Container/db.php:1.12 --- php4/pear/Cache/Container/db.php:1.11 Wed May 2 11:49:33 2001 +++ php4/pear/Cache/Container/db.php Fri May 4 01:14:20 2001 @@ -17,7 +17,7 @@ // | Chuck Hagenbuch <chuck@horde.org> | // +----------------------------------------------------------------------+ // -// $Id: db.php,v 1.11 2001/05/02 18:49:33 uw Exp $ +// $Id: db.php,v 1.12 2001/05/04 08:14:20 chregu Exp $ require_once 'DB.php'; require_once 'Cache/Container.php'; @@ -25,14 +25,14 @@ /** * PEAR/DB Cache Container. * -* WARNING: Other systems might or might not support certain datatypes of -* the tables shown. As far as I know there's no large binary -* type in SQL-92 or SQL-99. Postgres seems to lack any -* BLOB or TEXT type, for MS-SQL you could use IMAGE, don't know -* about other databases. Please add sugestions for other databases to +* WARNING: Other systems might or might not support certain datatypes of +* the tables shown. As far as I know there's no large binary +* type in SQL-92 or SQL-99. Postgres seems to lack any +* BLOB or TEXT type, for MS-SQL you could use IMAGE, don't know +* about other databases. Please add sugestions for other databases to * the inline docs. * -* The field 'changed' has no meaning for the Cache itself. It's just there +* The field 'changed' has no meaning for the Cache itself. It's just there * because it's a good idea to have an automatically updated timestamp * field for debugging in all of your tables. * @@ -44,36 +44,36 @@ * cachedata BLOB NOT NULL DEFAULT '', * userdata VARCHAR(255) NOT NULL DEFAUL '', * expires INT(9) NOT NULL DEFAULT 0, -* +* * changed TIMESTAMP(14) NOT NULL, -* +* * INDEX (expires), * PRIMARY KEY (id, cachegroup) * ) * * @author Sebastian Bergmann <sb@sebastian-bergmann.de> -* @version $Id: db.php,v 1.11 2001/05/02 18:49:33 uw Exp $ +* @version $Id: db.php,v 1.12 2001/05/04 08:14:20 chregu Exp $ * @package Cache */ class Cache_Container_db extends Cache_Container { - + /** * Name of the DB table to store caching data - * + * * @see Cache_Container_file::$filename_prefix - */ + */ var $cache_table = ''; /** * PEAR DB dsn to use. - * + * * @var string */ var $dsn = ''; /** * PEAR DB object - * + * * @var object PEAR_DB */ var $db; @@ -84,7 +84,7 @@ return new Cache_Error('No dsn specified!', __FILE__, __LINE__); } - $this->setOptions($options, array_merge($this->allowed_options), array('dsn', 'cache_table'))); + $this->setOptions($options, array_merge($this->allowed_options, array('dsn', 'cache_table'))); if (!$this->dsn) return new Cache_Error('No dsn specified!', __FILE__, __LINE__); @@ -113,29 +113,29 @@ $row = $res->fetchRow(); if (is_array($row)) $data = array($row['expires'], $this->decode($row['cachedata']), $row['userdata']); - else + else $data = array(NULL, NULL, NULL); - - // last used required by the garbage collection - // WARNING: might be MySQL specific + + // last used required by the garbage collection + // WARNING: might be MySQL specific $query = sprintf("UPDATE %s SET changed = (NOW() + 0) WHERE id = '%s' AND cachegroup = '%s'", $this->cache_table, addslashes($id), addslashes($group) ); - + $res = $this->db->query($query); - + if (DB::isError($res)) return new Cache_Error('DB::query failed: ' . DB::errorMessage($res), __FILE__, __LINE__); - return $data; + return $data; } /** * Stores a dataset. - * - * WARNING: we use the SQL command REPLACE INTO this might be + * + * WARNING: we use the SQL command REPLACE INTO this might be * MySQL specific. As MySQL is very popular the method should * work fine for 95% of you. */ @@ -180,9 +180,9 @@ $this->flushPreload(); if ($group) { - $query = sprintf("DELETE FROM %s WHERE cachegroup = '%s'", $this->cache_table, addslashes($group)); + $query = sprintf("DELETE FROM %s WHERE cachegroup = '%s'", $this->cache_table, addslashes($group)); } else { - $query = sprintf("DELETE FROM %s", $this->cache_table); + $query = sprintf("DELETE FROM %s", $this->cache_table); } $res = $this->db->query($query); @@ -193,7 +193,7 @@ function idExists($id, $group) { - $query = sprintf("SELECT id FROM %s WHERE ID = '%s' AND cachegroup = '%s'", + $query = sprintf("SELECT id FROM %s WHERE ID = '%s' AND cachegroup = '%s'", $this->cache_table, addslashes($id), addslashes($group) @@ -216,7 +216,7 @@ function garbageCollection($maxlifetime) { $this->flushPreload(); - + $query = sprintf('DELETE FROM %s WHERE (expires <= %d AND expires > 0) OR changed <= (NOW() - %d)', $this->cache_table, time(), @@ -225,10 +225,35 @@ $res = $this->db->query($query); + $query = sprintf('select sum(length(cachedata)) as CacheSize from %s', + $this->cache_table + ); + $cachesize = $this->db->GetOne($query); + //if cache is to big. + if ($cachesize > $this->highwater) + { + //find the lowwater mark. + $query = sprintf('select length(cachedata) as size, changed from %s order by changed DESC', + $this->cache_table + ); + $res = $this->db->query($query); + $keep_size=0; + while ($keep_size < $this->lowwater && $entry = $res->FetchRow(DB_FETCHMOD_ASSOC) ) + { + $keep_size += $entry[size]; + } + + //delete all entries, which were changed before the "lowwwater mark" + $query = sprintf('delete from %s where changed <= '.$entry[changed], + $this->cache_table + ); + $res = $this->db->query($query); + } + if (DB::isError($res)) { return new Cache_Error('DB::query failed: ' . DB::errorMessage($res), __FILE__, __LINE__); } } - + } ?>