Medical image retrieving and parallel balancing in cloud: Review article

NoSQL databases have recently experienced a surge in popularity, primarily driven by their capacity to effectively manage and process substantial amounts of data and their exceptional scalability capabilities. Nonetheless, it is important to acknowledge that these databases also bring about a set of trade-offs, particularly in relation to transaction consistency and overall performance. Consequently, it becomes imperative to have a comprehensive understanding of these trade-offs, as they play a pivotal role in making well-informed decisions when selecting a NoSQL database that aligns with the specific requirements of a given application. One of the primary challenges of NoSQL databases in supporting transaction consistency is the lack of full ACID support. While some NoSQL databases provide ACID guarantees for single operations, they may not offer the same level of consistency for multi-operation transactions. This can lead to inconsistencies when multiple operations are performed concurrently, impacting data integrity. The main objective of this study is to propose a novel model to provide strong consistency guarantees and offer the best performance for NoSQL databases. Therefore, this study proposed a transaction consistency model (PMC) for achieving the objectives. The proposed model uses existing techniques such as Two-Phase locking for isolation of single and multiple transactions and snapshot isolation for comparing versioning data on the replication node. The proposed model for transaction consistency (PMC) exhibited superior performance, scalability, and consistency when compared to alternative models. In terms of performance, the PMC model excelled by achieving higher throughput and lower latency than its counterparts. Moreover, the PMC model demonstrated exceptional scalability, being capable of accommodating a larger number of nodes than the other model. This ability to scale effectively is of utmost importance in modern distributed systems, where handling a larger number of nodes is crucial. Lastly, the PMC model distinguished itself by successfully upholding a high level of consistency, even under conditions of high load, which further solidifies its merit. The achievement of such a consistently high level of consistency can be attributed to the well-thought-out design and implementation of the PMC model. It is undeniable that the PMC model's superior performance, scalability, and consistency make it ready to apply in the realm of transaction processing systems. Keywords: NoSQL, Transactions, Consistency, NoSQL Transaction Consistency