Database design for movie catalog

Question

I'm designing a database for an exercise for class and am stuck in the design. In inventory system there are DVD's (divided into 3 Categories: TV, Music Vid, Movie). Within each of those categories it has its own subset of information - TV Category Info: TVInfo1, TVInfo2, TVInfo3 ; Movies Category: MInfo1, MInfo2, MInfo3, MInfo4 ; Music Video Category: MVInfo 1, MVInfo2.

I'm unsure how to incorporate that the Category Type has its own unique attributes dependent on each category. For my tables so far:

DVD(Title [PK], CategoryID[FK])

Category(CategoryID[PK], TYPE)

CatMovie(Title [PK,FK], CategoryID[PK,FK], MInfo1, MInfo2, MInfo3, MInfo4)

CatMV(Title [PK,FK], CategoryID[PK,FK],MVInfo 1, MVInfo2)

CatTV(Title [PK,FK], CategoryID[PK,FK],TVInfo1, TVInfo2, TVInfo3)

Not sure if that seems right. Thank you for any help.

Answer 1

As I can see, its just a simple database for a library of films. You can have design like this:

Now, following your specs, your title_mstr table contains all your titles. The title_category table will contain your categories( Movie or TV ). Then your info per category would be in category_info with reference to the title_category . This schema also includes a foreign key for each.

Here's the code:

-- -----------------------------------------------------
-- Table `title_category`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `title_category` (
  `title_cat_id` INT NOT NULL,
  `title_category_desc` VARCHAR(45) NULL,
  PRIMARY KEY (`title_cat_id`))
ENGINE = InnoDB;


-- -----------------------------------------------------
-- Table `title_mstr`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `title_mstr` (
  `title_id` INT NOT NULL AUTO_INCREMENT,
  `title_cat_id` INT NULL,
  `title_name` VARCHAR(100) NOT NULL,
  `title_desc` VARCHAR(45) NULL,
  `title_details` VARCHAR(45) NULL,
  PRIMARY KEY (`title_id`),
  UNIQUE INDEX `movie_name_UNIQUE` (`title_name` ASC),
  INDEX `title_cat_id_idx` (`title_cat_id` ASC),
  CONSTRAINT `title_cat_id`
    FOREIGN KEY (`title_cat_id`)
    REFERENCES `title_category` (`title_cat_id`)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB;


-- -----------------------------------------------------
-- Table `tape`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `tape` (
  `tape_id` INT NOT NULL,
  `tape_category_id` INT NULL,
  `movie_id` INT NULL,
  `tape_details` VARCHAR(45) NULL,
  PRIMARY KEY (`tape_id`))
ENGINE = InnoDB;


-- -----------------------------------------------------
-- Table `title_category_info`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `title_category_info` (
  `title_category_info_id` INT NOT NULL AUTO_INCREMENT,
  `title_cat_id` INT NULL,
  `title_category_info` VARCHAR(45) NULL,
  PRIMARY KEY (`title_category_info_id`),
  INDEX `title_cat_id_idx` (`title_cat_id` ASC),
  CONSTRAINT `title_cat_id`
    FOREIGN KEY (`title_cat_id`)
    REFERENCES `title_category` (`title_cat_id`)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB;


SET SQL_MODE=@OLD_SQL_MODE;
SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS;
SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS;

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