Distributed Databases A semijoin is which of the following? 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. 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 all of the 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. 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 all of the rows are returned. ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases Asynchronous technology can result in unsatisfactorily slow response time because the distributed DBMS is spending considerable time checking that an update is accurately and completely propagated across the network. True False True False ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases The purpose of timestamping is to avoid the use of locks. False True False True ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases A distributed database can use which of the following strategies? Partitioned into segments at different sites Partially or totally replicated across sites Totally centralized at one location and accessed by many sites All of these Partitioned into segments at different sites Partially or totally replicated across sites Totally centralized at one location and accessed by many sites All of these ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases Synchronization for pull replication is less disruptive and occurs only when needed by each site, not when a central master site thinks it is best to update. False True False True ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases Which of the following is a disadvantage of replication? 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. 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. Reduced network traffic ANSWER DOWNLOAD EXAMIANS APP