Distributed Databases A transaction manager is which of the following? All of these Maintains a log of transactions Maintains appropriate concurrency control Maintains before and after database images All of these Maintains a log of transactions Maintains appropriate concurrency control Maintains before and after database images ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases In a semijoin, only the joining attribute is sent from one site to another, and then only the required rows are returned. True False True False ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases A distributed database can use which of the following strategies? Partially or totally replicated across sites Totally centralized at one location and accessed by many sites Partitioned into segments at different sites All of these Partially or totally replicated across sites Totally centralized at one location and accessed by many sites Partitioned into segments at different sites All of these ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases Which of the following is true concerning a global transaction? The required data are located in at least one nonlocal site and the distributed DBMS passes the request to only the local DBMS. The required data are at one local site and the distributed DBMS routes requests as necessary. The required data are located in at least one nonlocal site and the distributed DBMS routes requests as necessary. The required data are at one local site and the distributed DBMS passes the request to only the local DBMS. The required data are located in at least one nonlocal site and the distributed DBMS passes the request to only the local DBMS. The required data are at one local site and the distributed DBMS routes requests as necessary. The required data are located in at least one nonlocal site and the distributed DBMS routes requests as necessary. The required data are at one local site and the distributed DBMS passes the request to only the local DBMS. ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases Which of the following is not one of the stages in the evolution of distributed DBMS? Unit of work Distributed request Remote unit of work Distributed unit of Work Unit of work Distributed request Remote unit of work Distributed unit of Work ANSWER DOWNLOAD EXAMIANS APP
Distributed Databases With asynchronous technology, if any copy of a data item is updated anywhere on the network, the same update is immediately applied to all other copies or it is aborted. False True False True ANSWER DOWNLOAD EXAMIANS APP