Oracle table and it's syntax and structure

Oracle table can be created using CREATE TABLE command. Table creation is a DDL language.
There is a syntax or structure to create table in Oracle database. For creating a table, table name must have to specify and column name, data type & size also should be mentioned.

Conditions of creating tables:

Bear in mind, two conditions must be fulfilled before creating any table in Oracle. Those conditions are:

• You must have the privileged to create table.
• A storage area must be needed to create any table.

Structure of creating table:

The structure or syntax of database table looks like the following:

CREATE TABLE [schema.] table
(column datatype [Default expr] [, ......]);

Description of the syntax of oracle table:

• schema: schema is a collection of objects. Schema objects refer to logical structure which includes tables, views, synonyms, sequences etc. In the syntax, schema is the same as table owner's name.
• table: it means the name of the table.
• column: it refers the name of the table's column.
• datatype: it refers the data type of the column and the datatype's size.
• DEFAULT expr: it specifies the default value of the column. Sometimes, some values are not put in the INSERT statement. That time, the default value is inserted to that column value.

Note:

• All CREATE TABLE syntax must be ended to a semicolon (;).
  

Example of creating table:

CREATE TABLE students(
 firstName  varchar2(20),
 lastName varchar2(20),
 age  number(2)
 );

In this example, a table named as "students" is created which has three columns: firstName, lastName and age. The syntax is ended by a semicolon (;).