Create table in Oracle

This article describes how to create a table in Oracle
The basic statement for creating a table is:

CREATE TABLE TABLE_NAME (
  kol_1 datatype {NULL|NOT NULL}
, kol_2 datatype {NULL|NOT NULL} 
, ..
, kol_n datatype {NULL|NOT NULL});

For example:

CREATE TABLE EMPLOYEE(
  ID        NUMBER        NOT NULL
, LASTNAME  VARCHAR2(200) NOT NULL
, FIRSTNAME VARCHAR2(100) NULL
, SALARY    NUMBER(9,2)
);

You can enhance the basic statement with all kind of features. For example:

Add primary key to table

, CONSTRAINT CONSTRAINT_NAME PRIMARY KEY (KOL_NAME) {USING INDEX TABLESPACE ts_name}

for example:
CREATE TABLE EMPLOYEE(
ID NUMBER NOT NULL
, ...
, constraint emp_pk primary key (ID)
);

Add check constraint to column:

, SALARY NUMBER(9,2) CHECK (SALARY>0 AND SALARY<1000000)

Add default value to column

, CREATE_DATE DATE DEFAULT SYSDATE

Create table based on sql

You can create a table based on the result of a sql.
For example:
Create table emp_copy as select id,firstname,lastname from employee;