public function getColumns($table)
{
$res = $this->query('SELECT * FROM "ALL_TAB_COLUMNS" WHERE "TABLE_NAME" = ' . $this->escapeText($table));
$columns = [];
while ($row = $res->fetch(TRUE)) {
$columns[] = ['table' => $row['TABLE_NAME'], 'name' => $row['COLUMN_NAME'], 'nativetype' => $row['DATA_TYPE'], 'size' => isset($row['DATA_LENGTH']) ? $row['DATA_LENGTH'] : NULL, 'nullable' => $row['NULLABLE'] === 'Y', 'default' => $row['DATA_DEFAULT'], 'vendor' => $row];
}
return $columns;
}