Friday, March 15, 2019

Serializability & Big data algorithms


Serializability theory is a mathematical tool with the capability of proving whether or not a scheduler works in the correct way (Zhang & Elmagarmid, 1993). The theory represents a concurrent execution as a set o0f transactions using a structure known as a history. The theory offers some properties that a history needs to meet for it to be serializable.  Consider a database d=(x, y, z), where you need to perform a series of transactions concurrently and the transactions include T1, T2….., Tn.  We need a way of knowing if the execution of the transactions took place in the right manner. An execution is correct if only it is similar to some serial execution of the transactions. We make use of logs to determine whether a concurrent execution was serializable. A log is a record of operations performed by each transaction.  The logs are central to the study of Serializability.
Two logs are equal if the executions that produced those logs leave the database the same state as it was initially.  For instance, each read operation should read from the same write operation in both of the logs or both logs should contain similar final writes.  Such logs are what we consider to be equivalent.  To find out if a log is serializable, we draw a serialization graph. We construct that graph as follows.  Let transactions T1 to Tn be nodes in the graph. There will be a directed graph between Ti to Tj if only for some x one of the following rules hold.
o   Ri[x]<wj[x] or
o   Wi[x]<rj[x] or
o   Wi[x]<wj[x].
The serializable theory states that a log M is serializable if and only if SG (M) (serialization graph) is acyclic (Microsoft.com, n.d). If we can determine a serial history, H, consistent with all edges in SG (Hi), we can conclude that Hi is equivalent to H. That is how the theory works in controlling concurrency and through that it can control both write and read operations as long as we can construct a serialization graph that is acyclic.

Why it is desirable to integrate Hadoop with big data to support big data analytic
Organizations are making use of real-time big data analytics to reorganize the landscape of their industries. They achieve that via the capturing, analyzing and storing volumes data previously unmanageable and from that analysis they can extract insights that can aid in supporting real-time business processes. They use Apache Hadoop in achieving that. Those businesses have realized that the use of Hadoop can help analyze big volumes of data without even paying regard to the chronology of that data as Hadoop provides excellent means to reorganize it perfectly.  Big data, Hadoop, and advanced analytics are very useful when integrating as they help in the formation of evolving analytics ecosystem (SAS Institute Inc., n.d). The integration of Hadoop in big data analysis helps organizations to have real-time analytics and consequently maximize their business values. For example with Hadoop, enterprises can analyze click stream trails of online clients in conjunction with historical buying patterns to provide personalized information to those customers.  The integration of Hadoop with big data helps provide deep analysis across a variety of datasets and this in turn improves outcomes in such cases.  It makes it possible to provide quick results, thus impacting the online transactions positively. There are analytic algorithms such as well as predictive analytics in Hadoop that aid big data analytics for big data analytics (TDWI, 2014).
Hadoop enables the performance of queries as well as data capacity to scale in a cost-effective manner across hundreds of two-socket servers based on Intel Xeon processor that has an attachment of direct storage drives. With the integration of Hadoop with big data, there is the provision of hot replication whereby multiple replicas of the often used data have automatic creation, and that avoids contention. A company can launch a popular product, and the product’s associated data is in continuous demand. Hundreds of replicas can have generation and manipulation without any bottlenecks with the help of Hadoop. Once the big data is in Hadoop, companies can perform traditional ETL tasks or normalizing, aggregating, cleansing and aligning data for their EDW by employing the MapReduce’s massive scalability (1105 Media Inc., 2014). Hadoop helps analytics to avoid transformational issues in their traditional ETLT as it enables the off-loading of ingestion, integration and transformation of unstructured data into their warehouses.
The technology’s integration into big data to support analysis is imperative as it is a suitable fit for iterative analysis that traditionally required the building of a data warehouse. The SQL on Hadoop does not replace data warehouse, but it offers an alternative to more expensive software and appliances needed for particular types of analysis (Marian & Thompson, 2014). The presence of SQL in Hadoop provides the way for enterprises to avoid the costly high-end business analysts and data scientists. Intense analysis of big data requires data to be present in the right place when in need. Moving data across systems is costly and time consuming, and that culminates to the slowing down of business operations. Hadoop makes the performance of big data analysis where the data sits without having to move it.


References
1105 Media Inc. (2014). TDWI checklist report// eight considerations for utilizing big data analytics with Hadoop.
Marian, G. & Thompson, W. (2014). Big data analytics and Hadoop. 
Microsoft.com (n.d). Serializability theory. 
SAS Institute Inc. (n.d). Hadoop. 
TDWI (2014). Eight considerations for utilizing big data analytics with Hadoop (On-Demand Webinar).
Zhang, A. & Elmagarmid, K. (1993). A theory of global concurrency control in multidatabase systems. VLDB journal, 2, 331-360.


Carolyn Morgan is the author of this paper. A senior editor at MeldaResearch.Com in legitimate essay writing service. If you need a similar paper you can place your order from research paper services.

No comments:

Post a Comment

Buy thesis Online for Cheap

We are keen on ensuring that, any time students Buy thesis Online papers from our website, they get good grades that align with their expec...