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  2. 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 .

  3. Wide and narrow data - Wikipedia

    en.wikipedia.org/wiki/Wide_and_narrow_data

    The pandas package in Python implements this operation as "melt" function which converts a wide table to a narrow one. The process of converting a narrow table to wide table is generally referred to as "pivoting" in the context of data transformations.

  4. Database model - Wikipedia

    en.wikipedia.org/wiki/Database_model

    A model is not just a way of structuring data: it also defines a set of operations that can be performed on the data. [1] The relational model, for example, defines operations such as select, project and join. Although these operations may not be explicit in a particular query language, they provide the foundation on which a query language is ...

  5. Nested set model - Wikipedia

    en.wikipedia.org/wiki/Nested_set_model

    The nested set model is a technique for representing nested set collections (also known as trees or hierarchies) in relational databases. It is based on Nested Intervals, that "are immune to hierarchy reorganization problem, and allow answering ancestor path hierarchical queries algorithmically — without accessing the stored hierarchy relation".

  6. 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]

  7. Bitemporal modeling - Wikipedia

    en.wikipedia.org/wiki/Bitemporal_Modeling

    Bitemporal modeling is a specific case of temporal database information modeling technique designed to handle historical data along two different timelines. [1] This makes it possible to rewind the information to "as it actually was" in combination with "as it was recorded" at some point in time.

  8. Relational model - Wikipedia

    en.wikipedia.org/wiki/Relational_model

    According to the relational model, a Relation's attributes and tuples are mathematical sets, meaning they are unordered and unique. In a SQL table, neither rows nor columns are proper sets. A table may contain both duplicate rows and duplicate columns, and a table's columns are explicitly ordered. SQL uses a Null value to indicate missing data ...

  9. NetCDF - Wikipedia

    en.wikipedia.org/wiki/NetCDF

    The Python programming language can access netCDF files with the PyNIO [14] module (which also facilitates access to a variety of other data formats). netCDF files can also be read with the Python module netCDF4-python, [15] and into a pandas-like DataFrame with the xarray module. [16]