oracle_23_hr_create.sql

DROP TABLE IF EXISTS job_grades;
DROP TABLE IF EXISTS job_history;

DROP TABLE IF EXISTS employees CASCADE CONSTRAINTS;
DROP TABLE IF EXISTS jobs;
DROP TABLE IF EXISTS departments;

DROP TABLE IF EXISTS locations;
DROP TABLE IF EXISTS countries;
DROP TABLE IF EXISTS regions; 

DROP SEQUENCE IF EXISTS locations_seq;
DROP SEQUENCE IF EXISTS departments_seq;
DROP SEQUENCE IF EXISTS employees_seq;

CREATE TABLE regions
    ( region_id      NUMBER 
       CONSTRAINT  region_id_nn NOT NULL 
    , region_name    VARCHAR2(25) 
    );

CREATE UNIQUE INDEX reg_id_pk
ON regions (region_id);

ALTER TABLE regions
ADD ( CONSTRAINT reg_id_pk
             PRIMARY KEY (region_id)
    ) ;

CREATE TABLE countries 
    ( country_id      CHAR(2) 
       CONSTRAINT  country_id_nn NOT NULL 
    , country_name    VARCHAR2(40) 
    , region_id       NUMBER 
    , CONSTRAINT     country_c_id_pk 
                 PRIMARY KEY (country_id) 
    ) 
    ORGANIZATION INDEX; 

ALTER TABLE countries
ADD ( CONSTRAINT countr_reg_fk
             FOREIGN KEY (region_id)
              REFERENCES regions(region_id) 
    ) ;


CREATE TABLE locations
    ( location_id    NUMBER(4)
    , street_address VARCHAR2(40)
    , postal_code    VARCHAR2(12)
    , city       VARCHAR2(30)
    CONSTRAINT     loc_city_nn  NOT NULL
    , state_province VARCHAR2(25)
    , country_id     CHAR(2)
    ) ;

CREATE UNIQUE INDEX loc_id_pk
ON locations (location_id) ;

ALTER TABLE locations
ADD ( CONSTRAINT loc_id_pk
             PRIMARY KEY (location_id)
    , CONSTRAINT loc_c_id_fk
             FOREIGN KEY (country_id)
              REFERENCES countries(country_id) 
    ) ;


CREATE SEQUENCE locations_seq
 START WITH     3300
 INCREMENT BY   100
 MAXVALUE       9900
 NOCACHE
 NOCYCLE;

CREATE TABLE departments
    ( department_id    NUMBER(4)
    , department_name  VARCHAR2(30)
    CONSTRAINT  dept_name_nn  NOT NULL
    , manager_id       NUMBER(6)
    , location_id      NUMBER(4)
    ) ;

CREATE UNIQUE INDEX dept_id_pk
ON departments (department_id) ;

ALTER TABLE departments
ADD ( CONSTRAINT dept_id_pk
             PRIMARY KEY (department_id)
    , CONSTRAINT dept_loc_fk
             FOREIGN KEY (location_id)
              REFERENCES locations (location_id)
     ) ;


CREATE SEQUENCE departments_seq
 START WITH     280
 INCREMENT BY   10
 MAXVALUE       9990
 NOCACHE
 NOCYCLE;

CREATE TABLE jobs
    ( job_id         VARCHAR2(10)
    , job_title      VARCHAR2(35)
    CONSTRAINT     job_title_nn  NOT NULL
    , min_salary     NUMBER(6)
    , max_salary     NUMBER(6)
    ) ;

CREATE UNIQUE INDEX job_id_pk 
ON jobs (job_id) ;

ALTER TABLE jobs
ADD ( CONSTRAINT job_id_pk
             PRIMARY KEY(job_id)
    ) ;


CREATE TABLE employees
    ( employee_id    NUMBER(6)
    , first_name     VARCHAR2(20)
    , last_name      VARCHAR2(25)
     CONSTRAINT     emp_last_name_nn  NOT NULL
    , email          VARCHAR2(25)
    CONSTRAINT     emp_email_nn  NOT NULL
    , phone_number   VARCHAR2(20)
    , hire_date      DATE
    CONSTRAINT     emp_hire_date_nn  NOT NULL
    , job_id         VARCHAR2(10)
    CONSTRAINT     emp_job_nn  NOT NULL
    , salary         NUMBER(8,2)
    , commission_pct NUMBER(2,2)
    , manager_id     NUMBER(6)
    , department_id  NUMBER(4)
    , CONSTRAINT     emp_salary_min
                     CHECK (salary > 0) 
    , CONSTRAINT     emp_email_uk
                     UNIQUE (email)
    ) ;

CREATE UNIQUE INDEX emp_emp_id_pk
ON employees (employee_id) ;


ALTER TABLE employees
ADD ( CONSTRAINT     emp_emp_id_pk
                     PRIMARY KEY (employee_id)
    , CONSTRAINT     emp_dept_fk
                     FOREIGN KEY (department_id)
                      REFERENCES departments
    , CONSTRAINT     emp_job_fk
                     FOREIGN KEY (job_id)
                      REFERENCES jobs (job_id)
    , CONSTRAINT     emp_manager_fk
                     FOREIGN KEY (manager_id)
                      REFERENCES employees
    ) ;

ALTER TABLE departments
ADD ( CONSTRAINT dept_mgr_fk
             FOREIGN KEY (manager_id)
              REFERENCES employees (employee_id)
    ) ;


CREATE SEQUENCE employees_seq
 START WITH     207
 INCREMENT BY   1
 NOCACHE
 NOCYCLE;


CREATE TABLE job_history
    ( employee_id   NUMBER(6)
     CONSTRAINT    jhist_employee_nn  NOT NULL
    , start_date    DATE
    CONSTRAINT    jhist_start_date_nn  NOT NULL
    , end_date      DATE
    CONSTRAINT    jhist_end_date_nn  NOT NULL
    , job_id        VARCHAR2(10)
    CONSTRAINT    jhist_job_nn  NOT NULL
    , department_id NUMBER(4)
    , CONSTRAINT    jhist_date_interval
                    CHECK (end_date > start_date)
    ) ;

CREATE UNIQUE INDEX jhist_emp_id_st_date_pk 
ON job_history (employee_id, start_date) ;

ALTER TABLE job_history
ADD ( CONSTRAINT jhist_emp_id_st_date_pk
      PRIMARY KEY (employee_id, start_date)
    , CONSTRAINT     jhist_job_fk
                     FOREIGN KEY (job_id)
                     REFERENCES jobs
    , CONSTRAINT     jhist_emp_fk
                     FOREIGN KEY (employee_id)
                     REFERENCES employees
    , CONSTRAINT     jhist_dept_fk
                     FOREIGN KEY (department_id)
                     REFERENCES departments
    ) ;


CREATE OR REPLACE VIEW emp_details_view
  (employee_id,
   job_id,
   manager_id,
   department_id,
   location_id,
   country_id,
   first_name,
   last_name,
   salary,
   commission_pct,
   department_name,
   job_title,
   city,
   state_province,
   country_name,
   region_name)
AS SELECT
  e.employee_id, 
  e.job_id, 
  e.manager_id, 
  e.department_id,
  d.location_id,
  l.country_id,
  e.first_name,
  e.last_name,
  e.salary,
  e.commission_pct,
  d.department_name,
  j.job_title,
  l.city,
  l.state_province,
  c.country_name,
  r.region_name
FROM
  employees e,
  departments d,
  jobs j,
  locations l,
  countries c,
  regions r
WHERE e.department_id = d.department_id
  AND d.location_id = l.location_id
  AND l.country_id = c.country_id
  AND c.region_id = r.region_id
  AND j.job_id = e.job_id 
WITH READ ONLY;



CREATE TABLE JOB_GRADES
        (grade_level VARCHAR2(3),
         lowest_sal NUMBER,
         highest_sal NUMBER);

COMMIT;