36 results about "Surrogate key" patented technology

A multi-dimensional OLAP query processing method oriented to a column store data warehouse is described. With this method, an OLAP query is divided into a bitmap filtering operation, a group-by operation and an aggregate operation. In the bitmap filtering operation, a predicate is first executed on a dimension table to generate a predicate vector bitmap, and a join operation is converted, through address mapping of a surrogate key, into a direct dimension table tuple access operation; in the group-by operation, a fact table tuple satisfying a filtering condition is pre-generated into a group-by unit according to a group-by attribute in an SQL command and is allocated with an increasing ID; and in the aggregate operation, group-by aggregate calculation is performed according to a group item of a fact table filtering group-by vector through one-pass column scan on a fact table measure attribute.

The invention relates to a query optimization method based on a connection index in a data warehouse. The steps are: creating a connection index of a fact table foreign key based on a dimension table proxy key; creating a connection index update strategy; when there is a predicate condition on the dimension table, through the connection After the index directly accesses the dimension table records, it needs to judge the predicate, and refer to the bitmap connection index to generate the connection bitmap index through dynamic bitmap connection index calculation; when the selection rate on the dimension table is very low, the dimension table bitmap is further compressed to improve the dimensionality. The cache level of the table bitmap calculation; the calculation method of the reference bitmap connection index based on the coprocessor memory calculation is adopted, and only the array and the bitmap data structure are used to calculate the simple memory address access. The invention can effectively improve the computing performance of the bitmap index, and can be combined with high-performance coprocessors such as GPU and Xeon PhiTM to accelerate the computing performance of the index, and can be widely used in the field of data warehouses.

The disclosed device provides idealized and reusable data source interfaces. The process of idealizing includes reengineering of an original data model using a surrogate key based model. The technique emphasizes readability and performance of the resulting operational data store. In, addition, the disclosed device provides a unique method for handling changes which allows for all types of changes to be automatically implemented in the operational data store by table conversion. Further the disclosed device provides inline materialization which supports a continuous data flow dependency chain. A continuous dependency chain is used to provide automated documentation as well as a dynamic paralleled transformation process.

The present invention relates to a method or system of generating a surrogate key using cryptographic hashing. One embodiment of the method of the present invention may have steps such as selecting a field or group of fields that is or are unique among all records in the database, for each record, extracting the data from the fields, concatenating the extracted data into an input message, running the input message through a hash generator, either in batches or one at a time, for testing purposes perhaps, and outputting a surrogate key.

The embodiment of the invention provides a method and a system for certificateless and pairing-free identity-based proxy signcryption. The method mainly comprises the following steps: a sender generates a private key and a public key thereof according to common parameters of the system and identity information parameters of the sender, generates proxy information based on the private key and the public key thereof, and sends the proxy information to a proxy; after the proxy information passes verification of the proxy, the proxy generates a proxy key, performs signcryption on a message needing to be sent based on the proxy key and the common parameters of the system to obtain a signcrypted message and an intermediate parameter, and sends the signcrypted message and the intermediate parameter to a receiver; and the receiver recovers the signcrypted message with the use of the intermediate parameter and the common parameters of the system to obtain a recovered message, and verifies the recovered message. The certificateless and pairing-free identity-based proxy signcryption scheme provided by the embodiment of the invention has both signature and encryption characteristics and has the feature of proxy. A key generation center only generates part of keys of a user, no certificate is needed, and the problem of key escrow is solved.

The disclosed device provides idealized and reusable data source interfaces. The process of idealizing includes reengineering of an original data model using a surrogate key based model. The technique emphasizes readability and performance of the resulting operational data store. In, addition, the disclosed device provides a unique method for handling changes which allows for all types of changes to be automatically implemented in the operational data store by table conversion. Further the disclosed device provides inline materialization which supports a continuous data flow dependency chain. A continuous dependency chain is used to provide automated documentation as well as a dynamic paralleled transformation process.

Embodiments of the present invention disclose a ciphertext processing method, apparatus, and system. The method includes: selecting, by a ciphertext sending end, a random secret value; calculating a private key of a local end according to a partial private key acquired by the local end and the random secret value; calculating a proxy key according to the private key of the local end and a public key publicized by a ciphertext receiving end, where the public key publicized by the ciphertext receiving end is calculated by the ciphertext receiving end according to a random secret value selected by the ciphertext receiving end and a system public parameter; and sending the proxy key, so that the ciphertext receiving end acquires a ciphertext obtained after a re-encryption operation is performed, according to the proxy key, on a ciphertext sent by the ciphertext sending end, and performs decryption. Existing defects of a ciphertext re-encrypting technology in a collusion aspect can be effectively avoided by adopting the embodiments of the present invention, thereby better ensuring information security, and meanwhile, implementation of the present invention avoids using a public key infrastructure (PKI), thereby having better extensibility.

The invention relates to an OLAP grouping aggregation method based on a function dependency relationship. The method comprises following steps: a function dependency tree structure among grouping attributes is defined, and the function dependency relationship between the grouping attributes and attributes among tables is defined; the grouping attribute of the GROUP BY clause is detected according to the grouping attribute function dependency tree; a query grouping attribute is divided into two subgroups which are formed by function dependency key attributes and other grouping attributes respectively; mode resolution is performed on a dimension table according to the function dependency relationship, wherein the dimension table adopts surrogate key mechanism and memory column storage mechanism; under the mechanisms of dimension table mode resolution and surrogate key index, grouping aggregation calculation further converts the subgroup attributes into function dependency attributes; after the grouping aggregation calculation is completed, the function dependency attributes are directly mapped to a memory offset address of related dimension table records according to function dependency attribute values to complete the operation of extracting other related grouping attributes. By means of the method, the size of grouping attributes can be reduced, and the Hash grouping calculating efficiency is increased.