Received December 13, 2018, accepted January 8, 2019, date of publication January 18, 2019, date of current version February 12, 2019. Digital Object Identifier 10.1109/ACCESS.2019.2893333 Performance of OnPrem Versus Azure SQL Server: A Case Study ROBERT GYŐRÖDi 1 , MARIUS IULIAN PAVEL 2 , CORNELIA GYŐRÖDi 1 , AND DOINA ZMARANDA 1 1 Department of Computer Science and Information Technology, University of Oradea, 410087 Oradea, Romania 2 Department of Computer Science and Information Technology, Faculty of Electrical Engineering and Information Technology, University of Oradea, 410087 Oradea, Romania Corresponding author: Robert Győrödi (rgyorodi@uoradea.ro) ABSTRACT This paper presents a comparative study between on-premises databases and cloud databases regarding the response time of the database. It focuses on presenting the advantages of storing data and applications in the cloud and, of course, on managing it in comparison with managing the same data and applications locally on one or more physical machines. A Microsoft Azure account was created to manage the database that is stored in the cloud. To achieve comparative results, a specific testing architecture that uses a Universal Windows Platform app was created and used. The application is running locally on multiple physical machines and works with that database to extract data, operate, and upload new data. For local tests, the database was stored locally on a server, with and without replication, and for cloud tests, it was stored into a server in Central US. This paper provides a practical approach that could be used for examining the performance of basic database operations when dealing with a different number of user situations. As a result of tests carried out, we will highlight the many advantages of cloud data storage, such as data accessibility, speed, security, automation, and disaster recovery, and we will also try to offer an answer to the most common and important question: ‘‘Why cloud?’’ INDEX TERMS Cloud, database, data storage, Microsoft Azure, Microsoft SQL Server, on-premises. I. INTRODUCTION Developing technologies and the growth of the amount of information people want to have access quickly from any- where at any time has led to the creation of cloud technology. Whether we are talking about pictures from the smartphone, a collection of .pdf, .doc files, software or maybe favorite movies, the data requirements keep increasing day by day. According to International Data Corporation, it is predicted that big data is growing at an annual rate of 60% for both structured and unstructured data [1]. In this context of increasing the complexity of user require- ments, cloud represents an alternative for storing, enabling access to files from everywhere and from any device that is connected to the internet and capable to process or dis- play those files. Consequently, the cloud is a good solu- tion that can assure safety of data, being almost always at hand [7]. Cloud computing is an Internet-based computing model which has gained significant popularity in the past sev- eral years as it provides on demand network access to a shared pool of configurable and often virtualized computing resources typically billed on a pay-as-you-use basis [6]. The term cloud computing is somewhat difficult to define precisely. A traditional definition is that it provides, at an actual monetary cost to the end-user, computation, software, data access and storage that requires no end-user knowledge about physical location and system configuration [5]. Currently, there are several used and well-known cloud providers available on the market, such as Amazon Web Services, Microsoft Azure, EnterpriseDB, Google Cloud Platform, MongoLab, RackSpace [1]. Amazon Web Services [9] has a variety of cloud-based database services, including MySQL, Oracle or SQL Server as relational database, and Amazon DynamoDB, the Amazon solid-state drive, on the NoSQL side [8]. The direct competi- tor of Amazon is Microsoft with its Microsoft Azure [10] that uses SQL Server technology to provide a relational database, allowing customers to either access an SQL database on its cloud, or hosted SQL server instances on virtual machines. Microsoft also emphasizes on hybrid databases that combine 15894 2169-3536  2019 IEEE. Translations and content mining are permitted for academic research only. Personal use is also permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications_standards/publications/rights/index.html for more information. VOLUME 7, 2019