38results about How to "Improve query processing efficiency" patented technology

The invention discloses a Hadoop-based mass stream data storage and query method and a Hadoop-based mass stream data storage and query system. The method comprises the following steps of: constructing a segmented column cluster type storage structure; sequentially storing stream data as column cluster records, compressing the column cluster records from front to back to obtain compressed data pages, writing each compressed data page into a piece of column cluster data, and simultaneously additionally writing the page outline information of the compressed data pages into the tail ends of the column cluster data to obtain an integrated data segment; and in the process of executing query statements, constructing a scan table according to filtering restraints by utilizing the page outline information at the tail ends of data segments to quickly filter the data.

An information retrieval system uses phrases to index, retrieve, organize and describe documents. Phrases are extracted from the document collection. Documents are the indexed according to their included phrases, using phrase posting lists. The phrase posting lists are stored in an cluster of index servers. The phrase posting lists can be tiered into groups, and sharded into partitions. Phrases in a query are identified based on possible phrasifications. A query schedule based on the phrases is created from the phrases, and then optimized to reduce query processing and communication costs. The execution of the query schedule is managed to further reduce or eliminate query processing operations at various ones of the index servers.

The utility model discloses an updating method for a moving object based on the road transportation network and GPS, aiming at enabling a central server to trace the former and current position of the moving objects. The utility model is characterized in that the moving object uses GPS to measure the latest running data continuously, through matching with the transportation network, the coordinate of the latitude and the longitude and the direction data are converted into the data format based on the road network, then the current running vector is compared with the running data submitted by the updating on the last position according to the principle of the inertia, and the position updating condition is determined, the current running vector of the moving object is reported to the central server only when the moving object does not keep running as the principle of the inertia. Additionally, the utility model optimizes the updating of the position in the road crossing, only one time position updating of the moving object is performed at most in the road crossing. The utility model has advantages of reducing the communication frequency and improving the data processing efficiency under the premises of securing the processing precision compared with the prior art.

The invention provides a query processing method and device. The method comprises the steps of: receiving a query statement comprising an XQuery query statement; performing grammar analysis on the query statement to generate a grammar tree, wherein the grammar tree is a tree representation form of grammar structures for inquiring source codes of the statement, and each node on the grammar tree expresses a grammar structure included in the query statement; performing sub tree splitting on the grammar tree to obtain sub trees, wherein the nodes included in each sub tree constitute a sub query statement; executing the sub query statements corresponding to the sub trees respectively in parallel to obtain sub query result sets corresponding to the sub trees respectively; merging the sub query result sets, and outputting a query result corresponding to the query statement. Sub tree splitting is performed on the grammar tree corresponding to the query statement to split the query statement into a plurality of sub query statements, the sub query statements are executed in parallel, and the execution results of the sub query statements are merged to obtain a query result of the query statement, so that the query processing efficiency is improved.

A system, method, and computer program product to improve XML query processing efficiency with virtual cursors. Structural joins are a fundamental operation in XML query processing, and substantial work exists on index-based algorithms for executing them. Two well-known index features—path indices and ancestor information—are combined in a novel way to replace at least some of the physical index cursors in a structural join with virtual cursors. The position of a virtual cursor is derived from the path and ancestor information of a physical cursor. Virtual cursors can be easily incorporated into existing structural join algorithms. By eliminating index I/O and the processing cost of handling physical inverted lists, virtual cursors can improve the performance of holistic path queries by an order of magnitude or more.

The invention relates to a joint query adaptive processing method for grid database, belonging to the field of joint query technology of grid database. The method sequentially comprises three parts, including a sampling calculation method, an optimal execution route acquisition method and a query pipeline dynamic adjustment method. The sampling calculation method comprises updating, on the basis of a cost model formula, query selectivity, inter-node network bandwidth and the processing cost value of nodes for single tuple, and calculating the processing cost of updating stages of each candidate plan; the optimal execution route acquisition method comprises finding out the minimal maximum flow route (the optimal execution route) between a starting point and an endpoint according to a connected graph formed by grids; if the optimal execution route is not the current execution route, the query plan is adjusted by the query pipeline dynamic adjustment method. Taking the dynamic characteristics of a grid environment in which the grid database is positioned into sufficient account, the method achieves high estimation precision of query processing cost, timely and accurately adjusts the query plan and effectively enhances the efficiency of query processing.

The invention provides a vehicle condition information query method and a vehicle condition information query device. The method comprises the steps that a management platform receives a query request sent from a user, wherein the query request comprises a vehicle logo and time information to be queried; the management platform acquires a local storage index table corresponding to the vehicle logo, and time logo, corresponding to the vehicle logo, of a vehicle condition information fragment uploaded to a cloud storage platform by vehicle-mounted equipment is stored in the local storage index table; the management platform determines the storage position of the vehicle condition information corresponding to the time information according to the local storage index table; the management platform acquires the vehicle condition information corresponding to the query request from the determined storage position. The storage position of the vehicle condition information to be queried is determined by the local storage index table, so when the vehicle condition information to be queried is determined to be stored at the cloud storage platform, the cloud storage platform can execute the operation for searching the vehicle condition information to be queried, the query operation of the cloud storage platform has larger certainty, and the query treating efficiency of the vehicle condition information is favorably improved.

A method, an apparatus, and a system for locating sensor data. The method includes the steps of: obtaining an index table; intercepting a query for sensor data in runtime; extracting a characteristic parameter from a query condition; locating a block identifier of matching sensor data storage blocks in the index table by using the characteristic parameter; and loading the storage blocks into a memory space of a working processor; where the index table contains mapping relationships between block identifiers of sensor data storage blocks and characteristic attributes of sensor data.

The invention provides a method for protecting position privacy based on a cache. According to the current position of a mobile user, information point data quite high in using possibility in future is cached, a client side first retrieves the local cache to solve user inquiry, the cache misses the hit, then the inquiry is sent to an LBS server, the processing rate of inquiry is increased, meanwhile, the communication frequency between the client side and the server is reduced, and user privacy protection is enhanced. The invention further provides a distance hierarchical tree index structureand a maximum distance replacement algorithm suitable for the cache. The rate can be effectively increased when the cache is retrieved, and the cache hit ratio is increased. The method is simple in realization process and easy to operate.

In one embodiment, a method includes receiving from a user of an online social network a search query input comprising a character string having a number of characters; accessing one or more verticals that each store objects associated with the online social network, where if the number of characters is less than or equal to a threshold number, then accessing a first set of verticals, and if the number of characters is greater than the threshold number, then accessing the first set of verticals and a second set of verticals; searching each accessed vertical to identify one or more objects associated with the vertical that substantially match the character string; and sending to the user references to the identified objects.

The invention provides a novel vehicle state management method based on a memory database, comprising the steps of: mapping a system memory into a virtual disc in a system by using a virtual memory disc technology, establishing a vehicle state database under a database storage path, transplanting the vehicle state database to the virtual memory disc, and establishing a vehicle state data table and a storage process according to the actual service requirements in a GPS management system so as to maintain vehicle state data in the GPS management system, wherein complicated logic relations can be realized with a storage process algorithm, without converting the complicated logic relations into relation of key and value in one-to-one correspondence. By use of the vehicle state management method based on the memory database, million orders of magnitude vehicle state management requirements in the GPS management system can be satisfied.

The invention discloses a data synchronization method and system, and belongs to the technical field of data synchronization. The method comprises the following steps: S1: obtaining a data operation request and the query time of data to be operated; S2: according to the corresponding query time, containing the data operation request in a request batch of a corresponding time slot; and S3: in a first storage unit, inquiring to obtain a data size contained in the time slot corresponding to one request batch, judging whether the data size is greater than a preset data size or not, dividing the data to be operated into a plurality of data batches by the preset data size as a unit if the data size is greater than the preset data size, transmitting each data batch to a second storage unit, and otherwise, transmitting all data to be operated to the second storage unit. The system comprises a first storage unit, a setting unit, an acquisition unit, a division unit, a query unit, a judgment unit and a processing unit. The technical scheme has the beneficial effects that query response speed is improved, and the use experience of a user is improved.

The invention relates to a market data processing method and device, a controller and a medium, and the method comprises the steps: obtaining market hot data, the market hot data being market data which can be updated within a preset time; storing the market hot data into a cache, and updating the market hot data in the cache in real time; Wherein the market hot data are converted into market colddata, and the market cold data are market data which are not updated within preset time; and storing the market cold data into a database. According to the invention, the throughput and reliability of market data processing are improved, and the delay of market data processing is reduced.

The invention relates to the technical field of embedded databases, in particular to a resource optimization method for structured query and a database query system. The resource optimization method for the structured query includes the steps of acquiring multiple query statements, and configuring hardware modules used for query processing according to the query statements. The database query system includes an instruction acquisition module for acquiring the query statements and a query processing module for configuring the hardware modules used for query processing according to the query statements. According to the resource optimization method for the structured query and the system, the hardware modules used for completing query processing can be dynamically adjusted according to the queuing condition of current query statements to be processed, so that the hardware module resources are reasonably arranged, and the query efficiency is improved.

The invention provides a monochrome mutual nearest neighbor query processing method for uncertain spatial data. The method includes the steps that an R tree is subjected to traversal, a nearest neighbor candidate set nnq of a query object q is obtained, and pruning nodes and objects in the process are preserved in a minimum pile Hrfn; objects in the nnq are inserted into the Hrfn; elements in the Hrfn are inserted into a set Sstemp; the Hrfn is subjected to traversal, and a reverse nearest neighbor candidate set rnnq of the q is obtained; the intersection of the nnq and the rnnq is solved to serve as the mutual nearest neighbor candidate set mnnq of the q; for each object o in the mnnq, the set Sstemp is subjected to traversal, and the nearest neighbor candidate set nno of the os is queried; the union set of the nno and the nnq is solved, and a probability calculation list of the os is obtained; the probability value of each object in the mnnq is calculated; the object with the probability value larger than the threshold value serves as the result and is returned. Compared with an existing method, the method is high in operation efficiency, low in I/O cost, short in query time and capable of improving query processing efficiency when used for processing corresponding query questions in LBS.

The invention discloses a multi-medicine sharing query method. The multi-medicine sharing query method comprises the following steps: constructing a query graph according to query conditions; segmenting the query graph to obtain a plurality of query sub-graphs; and querying in the knowledge graph according to the plurality of query sub-graphs and returning a drug use query result. According to the multi-medicine sharing query method, massive disease medicine data and complexity among the disease medicine data are managed in a knowledge graph mode, the query conditions are constructed into the query graph, and the query graph is used for searching in the data graph of the knowledge graph; the problems possibly confronted in complex multi-disease coexistence and multi-medicine sharing scenes of old patients are effectively solved, and the query processing efficiency is improved by segmenting the query graph into the query sub-graphs. The invention further discloses a mobile terminal and a storage medium.

The embodiment of the invention provides a moving object range query method, and belongs to the field of high-performance computing and the field of databases. The moving object range query method includes: caching, through a buffer, the moving object update data detected in real time and query data input by users; constructing a grid index for the moving object update data and the query data through a multi-core CPU to enable the moving object update data and the query data, which correspond to each other therein, to be stored in the same cells; and carrying out parallel computing on the moving object update data and the query data in each cell in a grid through a GPU (Graphics Processing Unit). According to the embodiment of the invention, characteristics of a large memory, the multi-core CPU and the GPU are fully exerted, thus the query processing efficiency of moving objects is improved, and user query demands of a location based service (LBS) under big data can be more satisfied.