The inherent characteristics of big data include four main aspects: large data volume, diverse data types, fast data processing speed and low data value density. Among them, the data volume refers to the data scale is very large, beyond the traditional database management system processing capacity; data type refers to a variety of data sources, different formats, to be processed using different technical means; data processing speed refers to the processing of data to be very fast to meet the needs of real-time data analysis and decision-making; low data value density refers to the existence of a lot of garbage data and useless data, to be processed through a large number of data analysis and decision-making processes. data and useless data, to be identified and filtered by data mining and other technical means.