Database Column

What Does Database Column Mean?

In the context of relational databases, a column is a set of data values, all of a single type, in a table. Columns define the data in a table, while rows populate data into the table.

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Most databases allow columns to contain complex data like images, whole documents or even video clips. Therefore, a column allowing data values of a single type does not necessarily mean it only has simple text values. Some databases go even further and allow the data to be stored as a file on the operating system, while the column data only contains a pointer or link to the actual file. This is done for the purposes of keeping the overall database size manageable – a smaller database size means less time taken for backups and less time to search for data within the database.

Techopedia Explains Database Column

A simple example is a table that stores customer information for a bank. The columns in this table may take the form of: Customer Name, Customer Phone Number, Customer Date of Birth, Customer ID, Address, City, Postal Code. A row of data is each horizontal set that contains data for for a customer fr all the columns listed. For example:

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.tableizer-table td {
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Customer Name Phone DoB ID Address City
1 Andrew Jones 202-555-2452 12-Jun-70 4356 12 Maple Drive New York

The term “field” is usually used interchangeably with “column,” but database purists prefer to use the word “field” to denote a particular value or single item of a column. Thus, a field is the intersection of a row and a column. In the bank example above, a field is formed by the intersection of a row with the column “Customer Name” to form “Andrew Jones.” However, this distinction is ignored by most.

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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.