SQL Database Table

The foundation of every Relational Database Management System is a database object called table. Every database consists of one or more tables, which store the database’s data/information. Each table has its own unique name and consists of columns and rows.

The database table columns (called also table fields) have their own unique names and have a pre-defined data types. Table columns can have various attributes defining the column functionality (the column is a primary key, there is an index defined on the column, the column has certain default value, etc.).

While table columns describe the data types, the table rows contain the actual data for the columns.

Here is an example of a simple database table, containing customers data. The first row, listed in bold, contains the names of the table columns:

Table: Customers

FirstName LastName Email DOB Phone
John Smith John.Smith@yahoo.com 2/4/1968 626 222-2222
Steven Goldfish goldfish@fishhere.net 4/4/1974 323 455-4545
Paula Brown pb@herowndomain.org 5/24/1978 416 323-3232
James Smith jim@supergig.co.uk 20/10/1980 416 323-8888

Now that we’ve learned what is a database table, we can continue with our sql tutorial and learn how to manipulate the data within the database tables.

CREATION TABLE:
create table customers(firstname varchar2(20),lastname varchar2(20),
2 Email varchar2(20),dob date,phone number(10));