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  2. Query by Example - Wikipedia

    en.wikipedia.org/wiki/Query_by_Example

    Query by Example (QBE) is a database query language for relational databases. It was devised by Moshé M. Zloof at IBM Research during the mid-1970s, in parallel to the development of SQL . [ 1 ] It is the first graphical query language, using visual tables where the user would enter commands, example elements and conditions.

  3. Database storage structures - Wikipedia

    en.wikipedia.org/wiki/Database_storage_structures

    insert efficient, with new records added at the end of the file, providing chronological order; retrieval efficient when the handle to the memory is the address of the memory; search inefficient, as searching has to be linear; deletion is accomplished by marking selected records as "deleted"

  4. Cursor (databases) - Wikipedia

    en.wikipedia.org/wiki/Cursor_(databases)

    In computer science, a database cursor is a mechanism that enables traversal over the records in a database. Cursors facilitate processing in conjunction with the traversal, such as retrieval, addition and removal of database records. The database cursor characteristic of traversal makes cursors akin to the programming language concept of iterator.

  5. Data retrieval - Wikipedia

    en.wikipedia.org/wiki/Data_retrieval

    Data retrieval means obtaining data from a database management system (DBMS), like for example an object-oriented database (ODBMS). In this case, it is considered that data is represented in a structured way, and there is no ambiguity in data. In order to retrieve the desired data the user presents a set of criteria by a query. Then the ...

  6. Information retrieval - Wikipedia

    en.wikipedia.org/wiki/Information_retrieval

    Information retrieval is the science [1] of searching for information in a document, searching for documents themselves, and also searching for the metadata that describes data, and for databases of texts, images or sounds. Automated information retrieval systems are used to reduce what has been called information overload. An IR system is a ...

  7. Database - Wikipedia

    en.wikipedia.org/wiki/Database

    Formally, a "database" refers to a set of related data accessed through the use of a "database management system" (DBMS), which is an integrated set of computer software that allows users to interact with one or more databases and provides access to all of the data contained in the database (although restrictions may exist that limit access to particular data).

  8. Document-oriented database - Wikipedia

    en.wikipedia.org/wiki/Document-oriented_database

    The central concept of a document-oriented database is the notion of a document.While each document-oriented database implementation differs on the details of this definition, in general, they all assume documents encapsulate and encode data (or information) in some standard format or encoding.

  9. Data dictionary - Wikipedia

    en.wikipedia.org/wiki/Data_dictionary

    The terms data dictionary and data repository indicate a more general software utility than a catalogue. A catalogue is closely coupled with the DBMS software. It provides the information stored in it to the user and the DBA, but it is mainly accessed by the various software modules of the DBMS itself, such as DDL and DML compilers, the query optimiser, the transaction processor, report ...