text: CREATE TABLE `wk_project_types` (
    `type_id` int(11) NOT NULL AUTO_INCREMENT,
    `parent_id` int(11) NOT NULL DEFAULT '0' COMMENT '父ID',
    `type_name` varchar(200) NOT NULL COMMENT '文档名称',
    `type_sort` int(11) NOT NULL DEFAULT '0' COMMENT '排序',
    `create_time` datetime DEFAULT NULL,
    `create_at` int(11) NOT NULL,
    `modify_time` datetime DEFAULT NULL,
    `modify_at` int(11) DEFAULT NULL,
    `version` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '当前时间戳',
    PRIMARY KEY (`type_id`),
    UNIQUE KEY `wk_project_types_id_uindex` (`type_id`),
    KEY `type_id_index` (`type_id`),
    KEY `type_sort_index` (`type_sort`),
    KEY `wk_project_types_parent_id_index` (`parent_id`)
  ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='项目分类表'