Database - Distrubuted Database
Database - Distrubuted Database
11. A distributed database is which of the following?
- A single logical database that is spread to multiple locations and is interconnected by a network
- A loose collection of file that is spread to multiple locations and is interconnected by a network
- A single logical database that is limited to one location.
- A loose collection of file that is limited to one location.
12. A semijoin is which of the following?
- Only the joining attributes are sent from one site to another and then all of the rows are returned.
- All of the attributes are sent from one site to another and then only the required rows are returned.
- Only the joining attributes are sent from one site to another and then only the required rows are returned.
- All of the attributes are sent from one site to another and then only the required rows are returned.
13. Which of the following is a disadvantage of replication?
- Reduced network traffic
- If the database fails at one site, a copy can be located at another site.
- Each site must have the same storage capacity.
- Each transaction may proceed without coordination across the network.
14. A distributed database can use which of the following strategies?
- Totally centralized at one location and accessed by many sites
- Partially or totally replicated across sites
- Partitioned into segments at different sites
- All of the above
15. Which of the following is not one of the stages in the evolution of distributed DBMS?
- Unit of work
- Remote unit of work
- Distributed unit of Work
- Distributed request