EMPLOYEE_ID NUMBER(6,0) No null 1 Primary key of employees table.
FIRST_NAME VARCHAR2(20 BYTE) Yes null 2 First name of the employee. A not null column.
LAST_NAME VARCHAR2(25 BYTE) No null 3 Last name of the employee. A not null column.
EMAIL VARCHAR2(25 BYTE) No null 4 Email id of the employee
PHONE_NUMBER VARCHAR2(20 BYTE) Yes null 5 Phone number of the employee; includes country code and area code
HIRE_DATE DATE No null 6 Date when the employee started on this job. A not null column.
JOB_ID VARCHAR2(10 BYTE) No null 7 Current job of the employee; foreign key to job_id column of the jobs table. A not null column.
SALARY NUMBER(8,2) Yes null 8 Monthly salary of the employee. Must be greater than zero (enforced by constraint emp_salary_min)
COMMISSION_PCT NUMBER(2,2) Yes null 9 Commission percentage of the employee; Only employees in sales department elgible for commission percentage
MANAGER_ID NUMBER(6,0) Yes null 10 Manager id of the employee; has same domain as manager_id in departments table. Foreign key to employee_id column of employees table. (useful for reflexive joins and CONNECT BY query)
DEPARTMENT_ID NUMBER(4,0) Yes null 11 Department id where employee works; foreign key to department_id column of the departments table