34 results about "Relational algebra" patented technology

A structured natural language query and knowledge system is provided to allow a user who lacks programming skills to enter a database query or a rule in the form of a structured natural language sentence. The scope of the sentence is preferably defined by an improved object relational query language, an object relational algebra, or both. Command and conditions that appear in natural language form are defined with corresponding formal query texts. A user is prompted to compose a structured natural language sentence using the defined commands and conditions. The user-selected command and its arguments appear as the verb phrase of a structured natural language sentence. The user-selected conditions and their parameters appear as the adjective phrases of the sentence. The sentence is parsed and changed into a translated formal query text for formal database query and rule processing.

A system is described that includes a data warehouse and a platform independent data warehouse load application operable to run on the system. The load application includes a sequencing unit configured to utilize timestamp data from incoming data to be stored in the data warehouse and a relational algebra of set operators to identify and sequence net changes between the incoming data and data previously stored within the data warehouse. The load application is configured to non-intrusively load the identified and sequenced net changes into the data warehouse.

A system disclosed includes a temporal data warehouse and a platform independent temporal data warehouse load application operable to run on the system. The load application uses timestamp data from incoming data in conjunction with a relational algebra of set operators to identify and sequence net changes between the incoming data and data previously stored within the data warehouse. The load application loads the identified and sequenced net changes into the data warehouse with relatively little intrusion into normal operation of the data warehouse. Optimizations, including but not limited to, distinct partitioning of the workload into parallel streams are selectable via metadata.

A query processing system of a database using multi-operation processing includes a task retrieval unit for retrieving relational algebra as tasks from a query tree, a unit for dividing retrieved tasks into groups for each relation of database, a synthetic relational operation unit for creating a synthetic relational operation by collecting tasks having common sub-expression for the grouped tasks into sub-groups and creating a task of a synthetic relational operation for each sub-group, wherein when there is a plurality of tasks of join operation in the grouped tasks, the synthetic relational operation unit further divides the grouped tasks into sub-groups for each common sub-expression of join operation, collects a plurality of tasks of the join operation into a sub-group, and creates a single task of a synthetic join operation by using logical union to concatenate each task of the join operation collected in the sub-group.

Techniques for constructing a software application are provided. A data model of the application is represented as a relational model. Control logic of the application is defined to specify each of a plurality of operations of the application as a mapping from a current state of the application data model and one or more current application inputs to a new state of the application data model and one or more application outputs, described by one or more relational algebra operations selected from the group consisting of a relation-complement operation, a disjunction operation and a conjunction operation.

The invention relates to a DFS (distributed file system) virtual directory organization and name-space management method including the following steps: file metadata of the file system is adopted according to a user inquiry request and a context to compute on-demand and dynamically generate the virtual directory in the relational algebra means so as to provide file serves matching the present context in hierachical form of the virtual file view for the user; the operations of creating, deleting, moving, renaming, opening, closing, reading, writing and cutting to files and operations of creating, deleting and renaming to context directories can be carried out in the virtual directory name-space. The invention has the beneficial effects that the adoption of the computed on-demand and dynamically generated virtual directory in a large-scale mass file storage system overcomes the defect that the traditional hierachical directory structure cannot provide services on demand, and provides the high effective file search and organization form. The adoption of file metadata including file attributes and contexts in the organization process of the virtual directory can actively provide file serves for the user according to the changing of the contexts.

A database enabled by the storage of information encoded in DNA molecules provides high information density, but the information is more difficult to access than conventional electronic storage media. A relational database is a way of organizing information by using multiple related tables. Perform relational algebra operations on relational databases to locate and manipulate information. The present disclosure provides techniques for implementing relational algebra operations on a relational database that uses DNA molecules to store information. The techniques of the present disclosure relate to the structure of DNA molecules used to store information and to the correlation between relational algebra operations and operations on DNA molecules.