Method, device and equipment for merging data in database

The embodiment of the invention discloses a method, a device and equipment for merging data in a database. The database has a plurality of data storage layers, the plurality of data storage layers having a time sequence. According to the scheme, the method comprises the steps of detecting whether data stored in a specified memory storage area reaches a set threshold value or not; if yes, data meeting set conditions are selected from the memory storage area, and the data meeting the set conditions are written into the data storage layer with the latest time sequence in the data storage layers to serve as a data subset; in the data storage layer with the latest time sequence, determining the total number of the existing data subsets and the occupied total storage space; and according to the total quantity and the total storage space, judging whether to merge the data in the data storage layer with the newest time sequence into the data storage layer with the second newest time sequence in the plurality of data