摘要:
Methods, database management systems (“DBMS”) and computer-readable media are provided for processing unbounded stream data using a traditional DBMS. Execution of a query that includes a data stream as a data source may be initiated. Tuples may be processed in accordance with the query as the tuples are received through the data stream until an indication is received that execution of the query should cease.
摘要:
One embodiment is a method that uses MapReduce and Relation Valued Functions (RVFs) with parallel processing to search a database and obtain search results.
摘要:
In continuous querying of a data stream, a query including query cycles can be initialized (310) on a query engine to analyze the data stream for desired information. The data stream can be processed (320) as segments, where a size of the segments is based on a user-defined parameter. The query cycles can be synchronized (330) with the segments of the data stream. A first segment can be analyzed (340) by performing the query on the first segment to obtain a first result. A query state of the query can be persisted (350) and the query operation can be rewound to begin a new query cycle. A second segment can be analyzed (360) in the new query cycle by performing the query on the second segment based on the first result.
摘要:
A representation of a flow network having vertices connected by arcs is provided. The vertices include a first set of vertices that provide flow to a second set of vertices over arcs connecting the first set and second set of vertices. A balancing procedure in the network is performed that includes redistributing flows on arcs incident on the second set of vertices. The balancing procedure includes selecting a batch of the vertices in the second set, and redistributing flows on arcs incident on the selected batch of vertices. The selecting and redistributing are repeated for other batches of vertices in the second set.
摘要:
Densest subgraphs of a graph are determined. The graph includes vertices and edges interconnecting the vertices. Each edge connects two of the vertices and has a weight. The vertices and the edges form subgraphs from which the densest subgraphs are determined as those subgraphs having densities greater than a threshold. Clusters at levels of a hierarchy are determined based on the densest subgraphs. Each cluster includes a set of the vertices and a set of the edges of the graph. Each level corresponds to a different density of the clusters. The hierarchy is ordered from a most-dense level of the clusters to a least-dense level of the clusters.
摘要:
To coordinate tasks executed by a plurality of threads that each includes plural task sections, a call of a mark primitive to mark a first point after a first of the plural task sections is provided. Also, a call of a second primitive is provided to indicate that a second of the plural task sections is not allowed to begin until after the plurality of threads have each reached the first point.
摘要:
The current application discloses a database management system that provides multiple-input, multiple-output-per-input user-defined-function-based operations. The database management system comprises at least one processor and electronic memory, a database-query processor, executed on a computer processor controlled by computer instructions stored in a computer-readable memory, that makes multiple calls to a multiple-input, multiple-output-per-input user-defined-function, in each call transmitting a next input to the multiple-input, multiple-output-per-input user-defined-function, and the multiple-input, multiple-output-per-input user-defined-function, executed on a computer processor controlled by computer instructions stored in a computer-readable memory, that uses three different memory buffers, the contents of which are maintained for three different time periods, to compute and return to the database-query processor multiple outputs in response to at least one of the multiple inputs.
摘要:
Densest subgraphs of a graph are determined. The graph includes vertices and edges interconnecting the vertices. Each edge connects two of the vertices and has a weight. The vertices and the edges form subgraphs from which the densest subgraphs are determined as those subgraphs having densities greater than a threshold. Clusters at levels of a hierarchy are determined based on the densest subgraphs. Each cluster includes a set of the vertices and a set of the edges of the graph. Each level corresponds to a different density of the clusters. The hierarchy is ordered from a most-dense level of the clusters to a least-dense level of the clusters.
摘要:
Nodes of a Bayesian network can be respectively associated with continuous queries. In response to a result of one of the continuous query changing, the continuous queries that are associated with nodes in the Bayesian network that are descendant of a node associated with the changed continuous query are evaluated.
摘要:
A data warehouse that operates to receive a spatial query and return a spatial result for the spatial query, the data warehouse comprises a regular database operating to receive and process a regular query and return a query result in response to the regular query. The data warehouse also comprises an interface layer implemented external to the regular database and operating to intercept the spatial query and translate the spatial query into the regular query for processing by the regular database. The regular database includes at least one spatial index that is accessed by the interface layer to translate the spatial query into the regular query for processing by the regular database.