A.Primary NameNode and standby NameNode

B.ZKFC and standby NameNode

C.Main NameNode and JournalNode

D.ZKFC and the main NameNode

A.More than 100 nodes

B.More than 200 nodes

C.Below 30 nodes

D.100-200 nodes

A.True

B.False

A.dropall

B.flushall

C.flushdb

D.dropdb

A.When deleting an external table, only delete the external table data without deleting the metadata

B.Create a normal table by default

C.When deleting a normal table, metadata and data are deleted at the same time

D.The essence of the external table is to associate the file path that already exists on the HDFS with the table