The FOREIGN KEY Clause : Foreign Key « Constraints « SQL Server / T-SQL Tutorial

1. SQL Server / T-SQL Tutorial
2. Constraints
3. Foreign Key

[CONSTRAINT c_name]
      [[FOREIGN KEY] (col_name1 [{, col_name2} ...]])
      REFERENCES table_name (col_name3 [{, col_name4} ...])
        [ON DELETE {NO ACTION|CASCADE|SET NULL|SET DEFAULT}]
         [ON UPDATE {NO ACTION|CASCADE|SET NULL|SET DEFAULT}]

14>
15> CREATE TABLE employee (emp_no INTEGER NOT NULL,
16>               emp_fname CHAR(20) NOT NULL,
17>               emp_lname CHAR(20) NOT NULL,
18>               dept_no CHAR(4) NULL,
19>       CONSTRAINT prim_empl PRIMARY KEY (emp_no))
20> GO
1>
2> CREATE TABLE myProject (
3>     emp_no INTEGER NOT NULL,
4>     project_no CHAR(4) NOT NULL,
5>     job CHAR (15) NULL,
6>     enter_date DATETIME NULL,
7>     CONSTRAINT prim_works PRIMARY KEY (emp_no, project_no),
8>     CONSTRAINT foreign_works FOREIGN KEY (emp_no) REFERENCES employee (emp_no))
9> GO
1>
2>
3> drop table myProject;
4> GO
1>
2> drop table employee;
3> GO
1>