Which three statements are true regarding the logical struct

第1题：

Which tow statements are most correct regarding opt-in models?（）

• A、A based opt-in model uses virtualized identifiers
• B、A based opt-in model uses hardware values as identifiers
• C、A logical server opt-in model uses virtualized identifiers
• D、A logical server opt-in model uses hardware values as identifiers

第2题：

Which three statements about the secure domain router are true？（）

• A、The logical router can span across chassis.
• B、The fabric and system controller module are shared by all logical routers.
• C、Each logical router has a distinct fabric and system controller module
• D、The logical router can share a route processor
• E、The logical router cannot share a route processor

第3题：

第4题：

Which two statements are true regarding L2TP? （）(Choose two.)

• A、Tunnels are initiated by the LAC
• B、Tunnels are initiated by the LNS
• C、By default, subscriber authentication occurs on the LNS
• D、By default, subscriber authentication occurs on the LAC

第5题：

Which statement is true regarding the INTERSECT operator?（）

• A、It ignores NULL values 
• B、Reversing the order of the intersected tables alters the result 
• C、The names of columns in all SELECT statements must be identical 
• D、The number of columns and data types must be identical for all SELECT statements in the query 

第6题：

Which three statements about OSPF areas are true?（）

• A、Areas introduce a boundary on the link - state updates.
• B、Areas are  logical definitions specific to any given router.
• C、All routers within an area have the exact link - state database.
• D、The calculation of the Dijkstra algorithm on a router is limited to changes within an area.
• E、The area designated router will always  have a priority of 0.

第7题：

Which of the following statements is true regarding the VERSIONS BETWEEN clause？（）  

• A、 The VERSIONS BETWEEN clause may be used in DML statements.
• B、 The VERSIONS BETWEEN clause may be used in DDL statements.
• C、 The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.
• D、 The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.

第8题：

Which two statements are true regarding the USING clause in table joins?（）

• A、It can be used to join a maximum of three tables 
• B、It can be used to restrict the number of columns used in a NATURAL join 
• C、It can be used to access data from tables through equijoins as well as nonequijoins 
• D、It can be used to join tables that have columns with the same name and compatible data types

第9题：

Which of the following a true statements regarding the use of VLANs to segment anetwork? （）

• A、They increase the size of collision domains
• B、They allow logical grouping of users by function.
• C、They can enhance network security.
• D、They increase the size of the broadcast domain while decreasing the number of collision domains.
• E、They increase the number of broadcast domains while decreasing the size of the broadcast domains.
• F、They simplify switch administration.

第10题：

Which two statements are true regarding B-tree indexs（）

• A、The leaf blocks in the index are doubly linked.
• B、The leaf node stores a bitmap for each key value.
• C、The rows with NULL value in key columns also have entries in the index.
• D、The deletion of a row from the table causes a logical deletion in index leaf block and the space becomesavailable for the new leaf entry