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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 ...
Cardinality (SQL statements)
The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database. [citation needed] These integrity constraints ensure compatibility between parts of the schema. All constraints are expressible in the same language. A database can be considered a structure in realization of the ...
SQL - Wikipedia ... SQL
Relational algebra is a branch of mathematics that studies the manipulation and analysis of data in relational databases. It defines a set of operations, such as selection, projection, join, and union, that can be applied to relations or sets of tuples. Learn more about the concepts and notation of relational algebra on Wikipedia, including the rename operation that changes the attribute name ...
Select (SQL) The SQL SELECT statement returns a result set of rows, from one or more tables. [1][2] A SELECT statement retrieves zero or more rows from one or more database tables or database views. In most applications, SELECT is the most commonly used data manipulation language (DML) command. As SQL is a declarative programming language ...
Database normalization
Relational model