If the disaster recovery center in the same city fails, the production center in cascading networking mode will lose all its backup sites.

Based on the understanding of the Generation stage of the lifecycle management of information and data, identify the 3 types of sources in which data can be generated.
(Multiple Choice)

According to the disaster tolerance effect, the disaster tolerance level can be divided into ____. (Multiple choice)

Some file types in the computer file system, such as XML, HTML, and Json, can be classified as semi-structured data according to the data type.

Regarding database-level disaster recovery, which of the following statement is wrong?