DROP TABLE D
DROP TABLE C
DROP TABLE B
DROP TABLE A
go

CREATE TABLE A
(
    ID        INT          PRIMARY KEY,
    LASTNAME  VARCHAR(32) NULL,
    FIRSTNAME VARCHAR(32) NULL,
    HIREDATE  DATETIME         NULL,
    BIRTHDATE DATETIME         NULL,
    SALARY    FLOAT        NOT NULL
)

CREATE TABLE B
(
    ID     DATETIME          PRIMARY KEY,
    NAME   VARCHAR(32) NULL
)

CREATE TABLE C
(
    ID     INT          PRIMARY KEY,
    NAME   VARCHAR(32) NULL
)

go