摘要:
An improved system and method for applying once a transaction delivered in a message published asynchronously in a distributed database is provided. In various embodiments, apply once messaging may be achieved for asynchronous publication by having a persistent log stored on a messaging server. A messaging server may receive an update message for a transaction to be published asynchronously in a distributed database, may generate a sequence number for the transaction in a message, and may log the update message with the sequence number in a log file persistently stored on the messaging server. The messaging server may then send an acknowledgement that the update message is published and may asynchronously publish the update message with the sequence number to subscribers. The publication may only succeed if there may not be any message tagged with a sequence number that has been previously published by the messaging server.
摘要:
The subject matter disclosed herein relates to bulk loading of data into a database comprising a plurality of database partitions. In one particular example, the database partitioning may be revised before addition of the new data to the partitions.
摘要:
An improved system and method for loading records into a partitioned database table is provided. A translation of records may be generated from a set of source partitions to a set of target partitions by generating a bipartite graph, determining a maximal matching using dynamic programming for a chain of nodes remaining in the bipartite graph after removing singleton edges, and generating a maximal matching after adding back the singleton edges for translation of records from the set of source partitions to the set of target partitions. The partition translation may be executed by traversing from top to bottom the set of source partitions and the set of target partitions in record key order to generate an optimal sequence of operations to transfer the records from the set of source partitions to the set of target partitions.
摘要:
An improved system and method for loading records into a partitioned database table is provided. A translation of records may be generated from a set of source partitions to a set of target partitions by generating a bipartite graph, determining a maximal matching using dynamic programming for a chain of nodes remaining in the bipartite graph after removing singleton edges, and generating a maximal matching after adding back the singleton edges for translation of records from the set of source partitions to the set of target partitions. The partition translation may be executed by traversing from top to bottom the set of source partitions and the set of target partitions in record key order to generate an optimal sequence of operations to transfer the records from the set of source partitions to the set of target partitions.
摘要:
A system and method for performing authentication are disclosed. The system may include a shared central processing server, a plurality of software components each residing in a corresponding point-of-sale (POS) workstation and an identity provider service. The server may reside at a merchant location and communicate with multiple POS workstations at the merchant location. The server may be configured to receive biometric information from each POS workstation. Each software component may communicate with a biometric sensor in communication with the corresponding POS workstation to receive biometric information. The identity provider service may be configured to communicate with the server, store registered biometric information and compare biometric information received from the server with one or more of the stored registered biometric information. One of the biometric sensor, a POS workstation and the server may convert a biometric image into a biometric template for comparison with the stored registered biometric information.
摘要:
The invention relates to a roll bending device for the control of profile and flatness in the rolling of metal plates or strips. In particular the invention relates to the well known principle of roll bending by using hydraulic cylinders to modify the load distribution between rolls of a rolling mill stand and a rolled stock e.g. a metal plate or a strip in order to control the profile and flatness of the metal plate or strip. A special design to allow safe roll bending even at large roll gauges is presented. The new design allows safe operation even at large roll gauges and high side loads.
摘要:
A method for encoding XML tree data that includes the step of encoding the semi-structured data into strings of arbitrary length in a way that maintains non-structural and structural information about the XML data, and enables indexing the encoded XML data in a way that facilitates efficient search and browsing.
摘要:
An improved system and method for publishing messages asynchronously in a distributed database is provided. Clusters of sequencer servers and broker servers may provide services for asynchronously publishing messages about topics including transactions for performing semantic operations on data in the distributed database system. A publisher client may send a message to a sequencer server that may add a sequence number to the message for the topic. The sequencer server may send the message to a primary broker server and a secondary broker server for asynchronous publication to subscribers of the topic of the message. If the primary broker server fails, the message sent to the secondary broker may be distributed to subscribers of the topic of the message. A subscriber client may receive the message and may order the messages received by sequence number for consumption by an application such as a subscriber database engine.
摘要:
A technique is described that reduces the complexity and resource consumption associated with performing record expiry in a distributed database system. In accordance with the technique, a record is checked to see if it has expired only when it has been accessed for a read or a write. If at the time of a read a record is determined to have expired, then it is not served. If at the time of a write a record is determined to have expired, then the write is treated as an insertion of a new record, and steps are taken to treat the insertion consistently with regard to the previous expired version. A background process is used to delete records that have not been written to or actively deleted by a client after expiration.
摘要:
A method for encoding XML tree data that includes the step of encoding the semi-structured data into strings of arbitrary length in a way that maintains non-structural and structural information about the XML data, and enables indexing the encoded XML data in a way that facilitates efficient search and browsing.