Method and device for querying trajectory data

Abstract

The invention discloses a method and device for querying track data, relates to the technical field of databases, and can shorten the time for querying track data. Including: establishing a spatio-temporal index and an inverted index for the track data in the spatio-temporal database, and the inverted index is used to form a first relationship correspondence table containing the corresponding relationship between each track and its associated index leaf node; The index leaf nodes included in the spatial area are sampled, wherein the number of index leaf nodes in the spatial area and the number of sampled index leaf nodes are determined; according to the sampled index leaf nodes and the first relationship corresponding table, the sampled index leaf nodes are determined. The corresponding relationship between each trajectory contained in the leaf node and the index leaf node associated with the trajectory forms a second relationship correspondence table; according to the number of index leaf nodes obtained by sampling in the space area and the number of index leaf nodes in the second relationship correspondence table The data, determine the unbiased estimation operator, calculate and determine the query result.

Description

technical field

[0001] The invention relates to the technical field of databases, in particular to a method and device for querying trajectory data. Background technique

[0002] It is well known that a trajectory contains a sequence of geographic locations. However, with the development of technology, in addition to the geographical location, the trajectory can also include time tags. That is to say, a trajectory can be composed of a series of geographical locations with time tags, which can be understood theoretically as "in three-dimensional space, a trajectory is composed of multiple data including time and geographic location". And the data of these trajectories can be stored in the spatio-temporal database for user query.

[0003] At present, users can query trajectory data through spatio-temporal indexing technology. First, create a spatio-temporal index. Such as figure 1 As shown, all trajectory data in the database are divided into small spatio-temporal regions...

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