Table

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What Does Table Mean?

A table is a named relational database data set that is organized by rows and columns. The relational table is a fundamental relational database concept because tables are the primary form of data storage.

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Columns form the table’s structure, and rows form the content. Tables allow restrictions for columns (i.e., allowed column data type) but not rows. Every database table must have a unique name. Most relational databases have naming restrictions For example, the name may not contain spaces or be a reserved keyword such as TABLE or SYSTEM.

Techopedia Explains Table

Relational tables store data in columns and rows. When creating a table, columns must be defined, but columns may be added or deleted after table creation. During this time, column data restrictions may or may not be defined. For example, when creating a CUSTOMER_MASTER table for storing customer information, definitions may be added, e.g., a DATE_OF_BIRTH column accepting dates only or a CUSTOMER_NAME column that may not be null (blank).

Table rows are the table’s actual data elements. In the CUSTOMER_MASTER table, the rows hold each customer record. Thus, a row consists of a data element within each table column. If a row value is not entered, the value is termed “null,” which does not have the same meaning as a zero or space.

Tables also have other table relationships that are defined by special columns, and the most prominent are primary and foreign keys. For example, the CUSTOMER_MASTER table has a CUSTOMER_ID column that is used to uniquely identify each table customer. If another table needs to refer to a certain customer, a corresponding column (also known as a foreign key) that references the CUSTOMER_MASTER table’s customer id may be inserted. Other tables do not need to store additional customer details that are already stored in the CUSTOMER_MASTER table.

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Margaret Rouse
Editor

Margaret jest nagradzaną technical writerką, nauczycielką i wykładowczynią. Jest znana z tego, że potrafi w prostych słowach pzybliżyć złożone pojęcia techniczne słuchaczom ze świata biznesu. Od dwudziestu lat jej definicje pojęć z dziedziny IT są publikowane przez Que w encyklopedii terminów technologicznych, a także cytowane w artykułach ukazujących się w New York Times, w magazynie Time, USA Today, ZDNet, a także w magazynach PC i Discovery. Margaret dołączyła do zespołu Techopedii w roku 2011. Margaret lubi pomagać znaleźć wspólny język specjalistom ze świata biznesu i IT. W swojej pracy, jak sama mówi, buduje mosty między tymi dwiema domenami, w ten…