Row (database)

Short description: Single data item in a relational database table

In the context of a relational database, a row—also called a tuple—represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns.[1] Each row in a table represents a set of related data, and every row in the table has the same structure.

For example, in a table that represents companies, each row would represent a single company. Columns might represent things like company name, company street address, whether the company is publicly held, its VAT number, etc. In a table that represents the association of employees with departments, each row would associate one employee with one department.

The implicit structure of a row, and the meaning of the data values in a row, requires that the row be understood as providing a succession of data values, one in each column of the table. The row is then interpreted as a relvar composed of a set of tuples, with each tuple consisting of the two items: the name of the relevant column and the value this row provides for that column.

Each column expects a data value of a particular type. For example, one column might require a unique identifier, another might require text representing a person's name, another might require an integer representing hourly pay in dollars.

Does not appear | Column 1 | Column 2

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Row 1  | Row 1, Column 1 | Row 1, Column 2
Row 2  | Row 2, Column 1 | Row 2, Column 2
Row 3  | Row 3, Column 1 | Row 3, Column 2

## See also

* Column (database)

## References

1. ↑ "What is a database row?" Cory Janssen, Techopedia, retrieved 27 June 2014

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Database management systems

Types|

* Object-oriented
* comparison
* Relational
* comparison
* Document-oriented
* Graph
* NoSQL
* NewSQL

Concepts|

* Database
* ACID
* Armstrong's axioms
* CAP theorem
* CRUD
* Null
* Candidate key
* Foreign key
* Superkey
* Surrogate key
* Unique key

Objects|

* Relation
* table
* column
* row
* View
* Transaction
* Transaction log
* Trigger
* Index
* Stored procedure
* Cursor
* Partition

Components|

* Concurrency control
* Data dictionary
* JDBC
* XQJ
* ODBC
* Query language
* Query optimizer
* Query rewriting system
* Query plan

Functions|

* Administration
* Query optimization
* Replication

Related topics|

* Database models
* Database normalization
* Database storage
* Distributed database
* Federated database system
* Referential integrity
* Relational algebra
* Relational calculus
* Relational database
* Relational model
* Object-relational database
* Transaction processing

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