Described are methods, systems and computer readable media for performance logging of complex query operations.

Embodiments of the present disclosure provide a data query method and apparatus, which implement a technical effect that data meeting a precision requirement is queried according to a user's requirement of for data precision. The method includes: receiving a query instruction that includes a query condition and query precision; determining a data partition that meets the query condition; determining a data sub-partition corresponding to the query precision from the data partition; and querying data in the data sub-partition to obtain a query result.

Example implementations disclosed herein can be used to build, maintain, and use a hash table distributed across the plurality multiple nodes in a multi-node computing system. The hash table can include data pages associated by corresponding pointers according to a tree data structure. The data pages include leaf data pages. Each leaf data page can be associated with a corresponding hash value and include a tag bitmap. When a transaction associated with a key is executed, a hash value and a tag value are generated based on the key. The leaf data pages can be searched using the hash value. A probability that a leaf data page includes the key can be determined based on a comparison tag value with the tag bitmap.

Described are methods, systems and computer readable media for data source refreshing.

A system includes reception of a first query at a first host, determination, at the first host, that the first query is associated with a first table, the first table including geographically-restricted data and a partitioning column storing identifiers of geographic restrictions, determination, at the first host and based on the partitioning column of the first table and on the first query, a first partition of the first table and a storage location of the first partition, and execution of the first query at the first host in conjunction with the storage location of the first partition.

A system that implements a scalable data storage service may maintain tables in a data store on behalf of storage service clients. The service may maintain table data in multiple replicas of partitions that are stored on respective computing nodes in the system. In response to detecting an anomaly in the system, detecting a change in data volume on a partition or service request traffic directed to a partition, or receiving a service request from a client to split a partition, the data storage service may create additional copies of a partition replica using a physical copy mechanism. The data storage service may issue a split command defined in an API for the data store to divide the original and additional replicas into multiple replica groups, and to configure each replica group to maintain a respective portion of the table data that was stored in the partition before the split.

An apparatus includes a processor component of a first node device caused to receive data block encryption data and an indication of size of an encrypted data block distributed to the first node device for decryption, and in response to the data set being of encrypted data: receive an indication of the quantity of sub-blocks within the encrypted data block, and a hashed identifier for each data sub-block; use the data block encryption data to decrypt the encrypted data block to regenerate data set portions from the data sub-blocks; analyze the hashed identifier of each data sub-block to determine whether all data set portions are distributed to the first node device for processing; and in response to a determination that at least one data set portion is to be distributed to a second node device for processing, transmit the at least one data set portion to the second node device.

A method of distributing data in a distributed storage system includes receiving a file, dividing the received file into chunks, and determining a distribution of the chunks among storage devices of the distributed storage system based on a maintenance hierarchy of the distributed storage system. The maintenance hierarchy includes maintenance levels, and each maintenance level includes one or more maintenance units. Each maintenance unit has an active state and an inactive state. Moreover, each storage device is associated with a maintenance unit. The determining of the distribution of the chunks includes identifying a random selection of the storage devices matching a number of chunks of the file and being capable of maintaining accessibility of the file when one or more maintenance units are in an inactive state. The method also includes distributing the chunks to storage devices of the distributed storage system according to the determined distribution.

Systems, methods, and devices for improved routing operations in a network computing environment. A system includes a virtual customer edge router and a host routed overlay comprising a plurality of host virtual machines. The system includes a routed uplink from the virtual customer edge router to one or more of the plurality of leaf nodes. The system is such that the virtual customer edge router is configured to provide localized integrated routing and bridging (IRB) service for the plurality of host virtual machines of the host routed overlay.

Systems, methods, and devices for incrementally refreshing a materialized view are disclosed. A method includes generating a materialized view based on a source table. The method includes merging the source table and the materialized view to generate a merged table to identify whether an update has been executed on the source table that is not reflected in the materialized view. The method includes, in response to detecting an update made to the source table that is not reflected in the materialized view, applying the update to the materialized view.