A Proxy Service for Multi-tenant Elastic Extension Tables - Transactions on Large-Scale-Data-and Knowledge-Centered Systems XX - page 32

SQL queries and backend data management code by utilizing the EETPS functions.
EETPS functions execute simple and complex queries including join operations, l-

tering on multiple properties, and ltering of data based on subqueries results. Addi-

tionally, we have presented ve sample algorithms for EETPS functions, and carried out

ve experiments for these functions to verify the effectiveness of EETPS. We classi ed

these experiments according to the complexity of the queries. The ve experiments

show comparisons between the response time of retrieving data from CTTs, VETs, and
both CTTs and VETs. The results of most of the experiments indicate improved per-
formance of queries from VET and CTT-and-VET using EETPS functions when
compared to queries using CTT (traditional physical tables). These results con

rm the
effectiveness of using EETPS and EET multi-tenant database and the associated three
types of database models, making the EET multi-tenant schema and EETPS suitable for
the software applications in general and SaaS applications in particular.
Our future work will focus on extending EETPS queries by adding GROUP BY and
ORDER BY query clauses, and applying join operations to more than two tables.
In addition, we plan to optimize data retrieval of EET by adding methods to determine
the optimal query execution plans, and caching the frequently used queries to reduce the
EETPS processing time and to minimize the use of EET database resources. We also
plan to perform experiments to evaluate the applicability of EETPS to unstructured and
semi-structured data. Furthermore, we plan to build the API for EETPS that will allow
the users to retrieve data from EET. We also plan to focus on the scalability of EET and
EETPS, and evaluate the performance in a scalable environment.

Acknowledgments. All authors wish to acknowledge UTS FEIT Research Seed Fund 2014 for
nancial support, and George Feuerlicht wishes to acknowledge the support of GA Č R grant
No. P403/11/0574.

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