enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Group by (SQL) - Wikipedia

    en.wikipedia.org/wiki/Group_by_(SQL)

    Typically, grouping is used to apply some sort of aggregate function for each group. [1] [2] The result of a query using a GROUP BY statement contains one row for each group. This implies constraints on the columns that can appear in the associated SELECT clause. As a general rule, the SELECT clause may only contain columns with a unique value ...

  3. pandas (software) - Wikipedia

    en.wikipedia.org/wiki/Pandas_(software)

    Pandas (styled as pandas) is a software library written for the Python programming language for data manipulation and analysis. In particular, it offers data structures and operations for manipulating numerical tables and time series .

  4. 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.

  5. Hierarchical Data Format - Wikipedia

    en.wikipedia.org/wiki/Hierarchical_Data_Format

    Hierarchical Data Format (HDF) is a set of file formats (HDF4, HDF5) designed to store and organize large amounts of data.Originally developed at the U.S. National Center for Supercomputing Applications, it is supported by The HDF Group, a non-profit corporation whose mission is to ensure continued development of HDF5 technologies and the continued accessibility of data stored in HDF.

  6. First normal form - Wikipedia

    en.wikipedia.org/wiki/First_normal_form

    In a hierarchical database, a record can contain sets of child records ― known as repeating groups or table-valued attributes.If such a data model is represented as relations, a repeating group would be an attribute where the value is itself a relation.

  7. List of relational database management systems - Wikipedia

    en.wikipedia.org/wiki/List_of_relational...

    List of Relational Database Management Systems (Alphabetical Order) Name License 4th Dimension: Proprietary Access Database Engine (formerly known as Jet Database Engine) Proprietary Actian Zen (PSQL) (formerly known as Pervasive PSQL) Proprietary Adabas D: Proprietary Airtable: Proprietary Altibase: Proprietary Amazon Aurora: Proprietary ...

  8. Table (database) - Wikipedia

    en.wikipedia.org/wiki/Table_(database)

    In a database, a table is a collection of related data organized in table format; consisting of columns and rows. In relational databases, and flat file databases, a table is a set of data elements (values) using a model of vertical columns (identifiable by name) and horizontal rows, the cell being the unit where a row and column intersect. [1]

  9. Grouped data - Wikipedia

    en.wikipedia.org/wiki/Grouped_data

    Yet another example of grouping the data is the use of some commonly used numerical values, which are in fact "names" we assign to the categories. For example, let us look at the age distribution of the students in a class. The students may be 10 years old, 11 years old or 12 years old. These are the age groups, 10, 11, and 12.