Where -ct generates the DDL statements according to object creation time.

ct在何处生成ddl语句由对象创建时间决定。

youdao

You will notice few things; the backup ID (eg 000000000000bb000002000d), dropped table start and end time (eg. 20040705150008) and the DDL for the dropped table.

您将注意到少数的几件事；备份 ID（比如 000000000000bb000002000d），表删除操作的开始和结束时间（比如 20040705150008）及被删除表的 DDL。

youdao

By making data types consistent within the DDL, there is less overhead associated with conversion of data at query run time.

通过在DDL中确保数据类型一致，在查询运行当中与数据转换相关的开销会比较小。

youdao