It is not possible to disable the primary key constraint.
It is possible to have more than one primary key constraint in a single table.
The primary key constraint can be referred by only one foreign key constraint.
The primary key constraint can be imposed by combining more than one column.
The non-deferrable primary key constraint creates an unique index on the primary key column if it is not already indexed.
第1题：
A. All the triggers for the table are disabled without changing any of the column names or column types in the table.
B. The primary key constraint on the EMPLOYEES table is disabled during redefinition.
C. VPD policies are copied from the original table to the new table during online redefinition.
D. You must copy the VPD policies manually from the original table to the new table during online redefinition.
第2题：
Which of following statements about testing software with data is (are) true?
Ⅰ.The primary purpose of such testing is to find errors.
Ⅱ.Such testing can demonstrate the existence of errors but can not demonstrate the absence of errors.
A．Neither
B．Ⅰ only
C．Ⅱ only
D．Ⅰ and Ⅱ
第3题：
Which of the following statements about testing software with data is (are) true?
Ⅰ.The primary purpose of such testing is to find errors.
Ⅱ.Such testing can demonstrate the existence of errors but cannot demonstrate the absence of errors.
A．Neither
B．I only
C．Ⅱonly
D．Ⅰand Ⅱ
第4题：
Which two statements are true about the primary address on an interface?（）
第5题：
Which of the following statements is TRUE about the primary system dump device?（）
第6题：
A. The same key is used for encryption and decryption.
B. It is commonly used to create digital certificate signatures.
C. It uses two keys: one for encryption and a different key for decryption.
D. An attacker can decrypt data if the attacker captures the key used for encryption.
第7题：
Which two statements about NTP version 4 are true？（）
第8题：
A.A primary key must exist for creation of a clustered index
B.A clustered index allows fulltext searching within InnoDB
C.The first unique index is always used as a clustered index and not a primary key
D.A clustered index provides direct access to a page containing row data
E.If no indexes exist, a hidden clustered index is generated based on row IDs
F.A primary key is used as a clustered index
G.A clustered index is a grouping of indexes from different tables into a global index for faster searching
第9题：
Which two statements are true about L2TP tunnels?（） (Choose two.)
第10题：
Which two statements regarding asymmetric key encryption are true？（）