How do i CHECK if a year is between 2000 and the current year?

I need to create a table for automobiles.

Each automobile has a year of manufacture. The year of manufacture must be between 2000 and the current year.

year_manufacture INTEGER CONSTRAINT nn_automobiles_year_manufacture NOT NULL 
                             CONSTRAINT ck_automobiles_year_manufacture 
                   CHECK ((year_manufacture>= 2000)AND(year_manufacture<= "current year")),

Solution

See if such a workaround helps.

Everything you've been already told stands. As you can't directly check the year against SYSDATE, create another column - THIS_YEAR - which won't be used anywhere in your code. It is automatically populated on each insert and gets current year.

Constraint (which can't be inline) then compares YEAR_MANUFACTURE with THIS_YEAR.

SQL> create table cars
  2    (id               number         constraint pk_cars primary key,
  3     name             varchar2(20)   not null,
  4     this_year        number(4)      default extract (year from sysdate),
  5     year_manufacture number(4),
  6     --
  7     constraint ch_year_manufacture check (year_manufacture between 2000 and this_year)
  8    );

Table created.

SQL>

Testing:

SQL> -- OK - after 2000, before 2019 (which is the current year)
SQL> insert into cars (id, name, year_manufacture) values (1, 'BMW', 2005);

1 row created.

SQL> -- Wrong - before 2000
SQL> insert into cars (id, name, year_manufacture) values (2, 'Mercedes', 1998);
insert into cars (id, name, year_manufacture) values (2, 'Mercedes', 1998)
*
ERROR at line 1:
ORA-02290: check constraint (SCOTT.CH_YEAR_MANUFACTURE) violated


SQL> -- Wrong - after 2019 (which is the current year)
SQL> insert into cars (id, name, year_manufacture) values (3, 'Cooper', 2020);
insert into cars (id, name, year_manufacture) values (3, 'Cooper', 2020)
*
ERROR at line 1:
ORA-02290: check constraint (SCOTT.CH_YEAR_MANUFACTURE) violated


SQL> -- OK - current year
SQL> insert into cars (id, name, year_manufacture) values (4, 'Opel', 2019);

1 row created.

SQL>
SQL> select * from cars;

        ID NAME                  THIS_YEAR YEAR_MANUFACTURE
---------- -------------------- ---------- ----------------
         1 BMW                        2019             2005
         4 Opel                       2019             2019

SQL>