Part 8. Q1.
1:There are three steps to complete this process:a. Plan& Setup: According to this step, we do a completeresearch with details about the cloud “with its supported & not supportedcharacteristics”. Therefore, we can know the essential changes in application thatmigration causes. b. improvement :After finding some differences in theprevious step, the developers improve the new database using these differences. c.
Examination : In this step, we isolate database activity and testers make teststo examine functionality and performance that concentrate on some necessarycriteria such as: Error handing, Logging, Security and Network issues.__________________________________________________________________Q1.2Theprocess is called “Clustering” that is technique is used to group similar recordscollectively in order to enable the end user to have a high level of what ishappening in the database.
In this process,we may think that each object as being introduced by some feature vector in an “n”dimensional space, “n” being the number of all the features thatused todescribe the objects for clustering. Then, the algorithm chooses “k” points randomlyin this vector space, these points work as the initial places of clusters. Thereafter,all objects are assigned individually to center they are closest to.
After that, we compute a new centerfor every cluster through averaging the feature vectors of all objects that areassigned to it. The process of re-constructing the centers and assigning theobjects is repeated until the process assembled. Moreover, after a finitenumber of iterations. The algorithm can be confirmed to converge.
The following are the most famousdata mining parameters:1. Association: Looking forpatterns where events are connected together.2. Path analysis (Sequence): Lookingfor patterns where one event causes another later event 3. Classification: Looking for the patterns4. Clustering: discovering and documentinggroups of new facts that not previously known visually.
Q2:Examples of Non-relational databases:Graph, Key-value store, Objectdatabase, Documentstore, Tabular,Triple/quadstore (RDF) database, Tuple store.Where/how, arethey used in the real world?The most common being MongoDB, Cassandra, DocumentDB, Coachbase, Redis,HBase and Neo4j. Why would youchoose to use a non-relational database over relational databases?Motives for this approach include:ü The design is simple and there is no need for dealing with the “impedancemismatch” between the schema that are based on rows and tables of a relationaldatabase and the object-oriented approach that is used to write applications.ü Finer control over availability: without the application downtime, Serverscan be removed or added.
ü Better “horizontal” scaling to clusters of machines, which usedto solve the problem when the number of concordant users skyrockets for the accessibleapplications via mobile devices and web. ü Capturing all types of data easily “Big Data” which areconsisted of semi-structured and unstructured data. ü Allowing for conducting a flexible database that can accommodate anynew type of data easily and quickly and is not torn by the changes in the contentstructure.
ü Cost: NoSQL databases always use cheap commodity servers’ clusters,but RDBMS tend to depend on storage systems and expensive proprietary servers. ü Speed: The data structures used by NoSQL databases such as JSONdocuments is different from the data structures used by default in the relationaldatabases. Actually, in NoSQL, operations are made faster than relationaldatabases because there is no need to join tables.