protected function _setPrimaryField()
{
if (self::$_primaryField != "") {
return;
// primary field already known
}
$res = $this->_db->executeSQL("SHOW COLUMNS FROM `{$this->_table}`");
if (!$res) {
throw new ModelException("Invalid query - " . $this->_db->getError());
}
$has_key = false;
$res = $this->_db->getResultset();
foreach ($res as $row) {
if ($row['Key'] == 'PRI') {
self::$_primaryField = $row['Field'];
$has_key = true;
}
self::$_metadata[$row['Field']] = $row['Type'];
}
if ($has_key) {
return;
}
throw new ModelException("Table {$this->_table} does not have primary key");
}
