earticle

영어

With the development of mobile internet and social network, the scale of structured data have been increasing to PB level and above rapidly, while the query performance is greatly reduce. The efficiency of query optimization on large-scale datasets is currently a research focus in both academia and industry. In this paper, we present a distributed data management method, designed to improve query performance, called KCSQ. KCSQ analyses historical SQL commands, deduces statistics using frequency and the coupling degree of tables and table columns, and confirms the key column based on statistical evidence. When importing new tables into the HDFS, the data are divided into different blocks according to their key column. Any query on these columns can reduce the amount of data to be queried and the number of working nodes and thus effectively improves the throughput rate of the system.