Methods and systems are provided herein for improved data filtering for use in user interfaces, data visualization, data exploration, and menu operations, which solve the aforementioned problems. Specifically, embodiments disclosed herein relate to improved data structuring for computer devices that provides efficient organization, filtering, and/or navigation in a user interface in order to improve how hierarchical data is displayed and filtered, particularly with regard to small displays or displays of data that aim to be efficient, intuitive, or easy to use.

In some examples, a system performs data deduplication using a deduplication fingerprint index in a hash data structure comprising a plurality of blocks, wherein a block of the plurality of blocks comprises fingerprints computed based on content of respective data values. The system merges, in a merge operation, updates for the deduplication fingerprint index to the hash data structure stored in a persistent storage. As part of the merge operation, the system mirrors the updates to a cached copy of the hash data structure in a cache memory, and updates, in an indirect block, information regarding locations of blocks in the cached copy of the hash data structure.

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

Techniques for using tree data structures to maintain a transactionally consistent set with support for time-travel queries are described. When a transaction commits, a new version of the tree data structure is created using a copy-on-write based method such that the tree shares internal nodes with previous trees to save space. This approach may be used in the implementation of a transactional data catalog in which the files that make up a table are stored in a transactional set.

A data processing method, having an index cache structure specified to a transaction in a mobile DBMS environment, comprising: recording only information on whether data is deleted/inserted on the an index cache without changing original index data while an inquiry process is progressed in response to a request to insert or delete data from an inquiry processor; and performing a change on data by changing the original index based on whether data recorded on the index cache upon a transaction commit is deleted.

Example implementation disclosed herein include techniques for methods, systems, and devices for a foster twin data structure. The data structure includes data pages, keys, and pointers. The pointers define hierarchical parent-child relationships among the data pages based on the keys. Transactions that result in inserts into the data pages are handled using foster twin data pages that split key ranges and the corresponding data records into two foster twin data pages. New pointers are added to the parent data page of the split data pages to indicate the new parent child relationship between the parent data page and the foster twin data pages. The old data page can be retired by adding a moved-bit and removing the old pointers from the parent data page to guide concurrent transaction and prevent future transactions.

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

One embodiment sets forth a technique for generating a tree structure within a computer memory for storing sparse data. The technique includes dividing a matrix into a first plurality of equally sized regions. The technique also includes dividing at least one region in the first plurality of regions into a second plurality of regions, where the second plurality of regions includes a first region and one or more second regions that have a substantially equal number of nonzero matrix values and are formed within the first region. The technique further includes creating the tree structure within the computer memory by generating a first plurality of nodes representing the first plurality of regions, generating a second plurality of nodes representing the second plurality of regions, and grouping, under a first node representing the first region, one or more second nodes representing the one or more second regions.

An example operation may include one or more of receiving a data block for storage on a blockchain from an orderer node, the data block comprising a full-step hash of a storage request and a reduced-step hash of the storage request, performing an approximate hash verification on the data block based on the reduced-step hash of the storage request included in the data block, and in response to a success of the approximate hash verification, committing the data block among a hash-linked chain of data blocks stored within a distributed ledger of a blockchain.

Techniques are disclosed relating to building an in-memory multi-level data structure useable to determine presence or absence of key ranges in files consisting of database records. In various embodiments, a computer system operates a database, including maintaining a set of records having a set of corresponding keys that are accessible in key-sorted order and generates a multi-level data structure that facilitates key range lookups against the set of records. The generating may include accessing ones of the set of keys in key-sorted order and determining, for a particular accessed key that includes a set of characters, an intermediate level within the multi-level data structure and a subset of the characters of the particular accessed key for insertion. The computer system may insert, starting at the intermediate level, information that identifies the subset of characters, with the inserting being performed without traversing any levels before the intermediate level.