33 results about "Hash join" patented technology

The hash functions using elliptic curve cryptography are hash functions that are produced using both an elliptic curve and a twist of the elliptic curve. Hash points are assigned values that either correspond to points on the elliptic curve or to points on the twist, depending upon whether the scalar value of the corresponding message block produces a quadratic residue or a quadratic non-residue when substituted as the x-value into the elliptic curve equation. The corresponding hash point x-coordinates are concatenated to form the hash bit string. The hash points may be doubled, and the hash functions may be applied to multimedia data by applying a media compression method to the message data before computing the hash points.

The present invention discloses the use of computers to link data records. Data records in the first plurality of data records and the second plurality of data records are hashed. Based on the hash, the first plurality of data records and the second plurality of data records are assigned to the first group and the second group, respectively. Associated pairs of packets from the first packet and the second packet are provided to threads executing on the computer processor, and different pairs are provided to different threads. Threads operate on group pairs in parallel to determine whether to join the records in the group. If the hashes associated with the data records match, the thread concatenates the two data records under consideration together. Outputs the connected data records.

A hash mixing acceleration system and a hash connection method using the same. The system includes: a hash partition accelerator, which is configured to be integrated on the memory, and is used to accelerate the processing of the hash join partition stage. The hash partition accelerator includes: a hash unit used to read multiple block relational tables from memory Tuples, and then process the keys of multiple tuples in parallel to generate multiple hash indexes; the histogram unit is used to update multiple copies of the histogram data stored in the histogram unit in parallel according to multiple hash indexes , and the updated copies are integrated into a form of data consistency; the shuffling unit is used to determine the location of each tuple stored in the target address array based on multiple hash indexes, and copy the tuples in the relational table to An array of targets; the host processor that handles the construction and probing phases of the hash join. Compared with existing processors, the disclosed hybrid acceleration system can greatly improve the energy efficiency of hash join processing.

The invention provides a method and device for training a deep neural network based on a hash coding layer. Wherein, the method includes: obtaining a pre-trained neural network model, the neural network model includes a basic feature layer; after the basic feature layer in the neural network model, inserting the first fully connected layer used for hash coding linear mapping and used as an activation function; insert a second fully-connected layer after the hash-encoded layer as an output layer; train the weights of the first fully-connected layer and the second fully-connected layer. The present invention uses the hash coding layer as the activation function of the deep neural network training, and trains the neural network through the stochastic gradient descent method to achieve the overall optimization, and directly trains the output binary coded model without relaxing the optimization conditions change.

The invention provides a data connection method across a data center of an HDFS (Hadoop Distributed File System). The method comprises the following steps that: a coordination node acquires the IP (Internet Protocol) addresses of metadata nodes from a configuration file after receiving a data connection operating request, establishes connection with the metadata nodes in the configuration file one by one, and acquires metadata information about a requested metadata node when a requested table is inquired in a current metadata node; the requested node filters data of the requested node according to information about requested data, screens the requested data of the requested node, and transmits the size of a result set saved by the requested node to the coordination node; the coordination node informs small result set nodes to transmit result sets saved by the small result set nodes to all large result set nodes; all the large result set nodes perform Hash join on the result sets of the large result set nodes and the result sets transmitted by all the small result set nodes to obtain result records; and the coordination node aggregates the result records. Through the method and a system, data connection across the data center can be realized.

The invention belongs to the technical field of databases, and specifically relates to a method, a terminal and a medium for pushing down a predicate in an SQL connection operation, comprising the following steps: Hash joining a fact table and a dimension table, generating a Hash table according to the dimension table, The fact table generates a fact table histogram; according to the Hash table and the N predicate histogram regions obtained by the fact table histogram, the N is a positive integer; the N predicate histogram regions are converted into predicates, and push down the predicate to the data storage layer. Compared with the minimum value / maximum value and complete Hash push-down, the present invention can improve the data filtering ability according to the histogram of the fact table, thereby improving the calculation efficiency of the storage layer.

A method for detecting and handling skew and spillover in in-memory hash join operations. To improve the detection of skew and spillover in parallel processing systems, a Poisson distribution of unique hash values to Units of Parallelism (UoPs) is employed to determine the number of rows per UoP and in turn, the potential of spillover at a UoP. Hash join plan options can be selected or adjusted to reduce the likelihood of spillover.