datatable

A datatable is a two-dimensional data structure that organizes data in rows and columns, with each column representing a variable and each row an observation. Columns have names and data types; rows contain values aligned to those types. Datatables are used to store, manipulate, and display tabular data in many computing contexts, from databases and spreadsheets to in-memory data structures in programming languages.

In databases, tables are the primary storage; in programming, a datatable object offers operations such as select, filter, sort, group, and join. Most implementations provide indexing and efficient access to subsets.

Notable implementations include the DataTables JavaScript library for rendering and manipulating HTML tables on web pages, the data.table package in R for fast, memory-efficient data frames, and the Python datatable library for large data sets. The .NET framework provides a DataTable class as part of its data access API.

Common operations include filtering rows by conditions, sorting by one or more columns, computing aggregations, merging with other tables, and handling missing values. Performance considerations include memory usage and whether data is stored row-wise or column-wise; some systems employ columnar storage for analytic workloads.

In practice, the term datatable is used broadly; depending on language or library, the API and capabilities vary.