Research On Temporal Information Retrieval Method Of Relational Database

Temporal is an important dimension of describing things.Many data in database contain temporal attributes.Traditional keyword retrieval in relational databases focuses on data text attributes,which cannot meet the user's retrieval needs for temporal information.Aiming at this problem,the temporal information retrieval method based on relational database is studied.The main work includes the following aspects:(1)Aiming at the lack of considering the temporal properties of nodes and the strength of inter-node correlation in the traditional retrieval data graph model,a temporal data graph model based on relational database is proposed.The tuple records in the relational model of the relational database ware mapped to the nodes in the graph,the association between tuples ware mapped to the edges in the graph,the effective time of the association between tuples was the time attribute of the edges in the graph,and the weight of the edges in the graph was assigned according to the degree of association between the nodes.A temporal data graph model based on temporal information retrieval in relational database is constructed.The retrieval efficiency of BANKS,STAR and BLINKS in temporal data graph model and traditional model is compared.The experimental results show that the retrieval algorithm based on temporal data graph model had higher precision and recall rate,and the retrieval efficiency of BANKS algorithm is higher than other algorithms in comparison.(2)To further improve the retrieval efficiency of BANKS algorithm and make the retrieval results more consistent with the time constraints of temporal information retrieval,a T-BANKS retrieval algorithm based on temporal data graph is proposed.Firstly,the algorithm searches the single-source shortest-time path of key temporal nodes in the constructed temporal data graph.Secondly,uses FindBase root-seeking algorithm to sort the shortest-time path set of each key temporal node to find the root node of the minimum temporal Steiner tree.Finally,in the process of constructing the minimum temporal Steiner tree,the temporal nodes and edges that do not meet the time constraints are filtered.Returns the time-constrained search results.The experimental results show that the T-BANKS retrieval algorithm based on temporal data graph improves the precision,recall and time performance of temporal information retrieval.(1)A temporal information retrieval system based on relational database is developed by combining the temporal data graph model and T-BANKS retrieval algorithm.The main function modules of the system include the generation of temporal data graph and the retrieval of temporal information.The application of the system in the NBA temporal data retrieval shows the feasibility and validity of the system in retrieving temporal information.