/**
* 设置当前数据表的元数据
*/
protected function _setupMeta()
{
$table_name = $this->getFullTableName();
$this->_cache_id = $this->_conn->getID() . '-' . $table_name;
if (isset(self::$_meta[$this->_cache_id])) {
return;
}
$cached = Q::getIni('db_meta_cached');
if ($cached) {
// 尝试从缓存读取
$policy = array('encoding_filename' => true, 'serialize' => true, 'life_time' => Q::getIni('db_meta_lifetime'), 'cache_dir' => Q::getIni('runtime_cache_dir'));
$backend = Q::getIni('db_meta_cache_backend');
$data = Q::getCache($this->_cache_id, $policy, $backend);
if (is_array($data) && !empty($data)) {
self::$_meta[$this->_cache_id] = $data[0];
self::$_fields[$this->_cache_id] = $data[1];
return;
}
}
// 从数据库获得 meta
$meta = $this->_conn->metaColumns($table_name);
$fields = array();
foreach ($meta as $field) {
$fields[$field['name']] = true;
}
self::$_meta[$this->_cache_id] = $meta;
self::$_fields[$this->_cache_id] = $fields;
$data = array($meta, $fields);
if ($cached) {
// 缓存数据
Q::setCache($this->_cache_id, $data, $policy, $backend);
}
}
