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CREATE TABLE "HR"."DEPARTMENTS" 
  (	"DEPARTMENT_ID" NUMBER(4,0), 
"DEPARTMENT_NAME" VARCHAR2(30 BYTE) CONSTRAINT "DEPT_NAME_NN" NOT NULL ENABLE, 
"MANAGER_ID" NUMBER(6,0), 
"LOCATION_ID" NUMBER(4,0), 
 CONSTRAINT "DEPT_ID_PK" PRIMARY KEY ("DEPARTMENT_ID")
 USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 NOLOGGING COMPUTE STATISTICS 
 STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
 TABLESPACE "EXAMPLE"  ENABLE, 
 CONSTRAINT "DEPT_MGR_FK" FOREIGN KEY ("MANAGER_ID")
  REFERENCES "HR"."EMPLOYEES" ("EMPLOYEE_ID") ENABLE, 
 CONSTRAINT "DEPT_LOC_FK" FOREIGN KEY ("LOCATION_ID")
  REFERENCES "HR"."LOCATIONS" ("LOCATION_ID") ENABLE
  ) PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS NOLOGGING
 STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
 TABLESPACE "EXAMPLE" ;

  COMMENT ON COLUMN "HR"."DEPARTMENTS"."DEPARTMENT_ID" IS 'Primary key column of departments table.';

  COMMENT ON COLUMN "HR"."DEPARTMENTS"."DEPARTMENT_NAME" IS 'A not null column that shows name of a department. Administration,
Marketing, Purchasing, Human Resources, Shipping, IT, Executive, Public
Relations, Sales, Finance, and Accounting. ';

  COMMENT ON COLUMN "HR"."DEPARTMENTS"."MANAGER_ID" IS 'Manager_id of a department. Foreign key to employee_id column of employees table. The manager_id column of the employee table references this column.';

  COMMENT ON COLUMN "HR"."DEPARTMENTS"."LOCATION_ID" IS 'Location id where a department is located. Foreign key to location_id column of locations table.';

  COMMENT ON TABLE "HR"."DEPARTMENTS"  IS 'Departments table that shows details of departments where employees
work. Contains 27 rows; references with locations, employees, and job_history tables.';

 CREATE UNIQUE INDEX "HR"."DEPT_ID_PK" ON "HR"."DEPARTMENTS" ("DEPARTMENT_ID") 
 PCTFREE 10 INITRANS 2 MAXTRANS 255 NOLOGGING COMPUTE STATISTICS 
 STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
 TABLESPACE "EXAMPLE" ;

 CREATE INDEX "HR"."DEPT_LOCATION_IX" ON "HR"."DEPARTMENTS" ("LOCATION_ID") 
 PCTFREE 10 INITRANS 2 MAXTRANS 255 NOLOGGING COMPUTE STATISTICS 
 STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
 TABLESPACE "EXAMPLE" ;