MySQL SQL 오류 errno : 121

CREATE TABLE `users` (
  `UID` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
  `username` VARCHAR(45) NOT NULL ,
  `password` VARCHAR(100) NULL ,
  `name` VARCHAR(100) NULL ,
  `gender` BIT NULL ,
  `email` VARCHAR(255) NULL ,
  `phone` VARCHAR(30) NOT NULL ,
  `verified` BIT NOT NULL DEFAULT 0 ,
  `time_zone` INT NULL ,
  `time_register` DATETIME NULL ,
  `time_active` DATETIME NULL ,
  PRIMARY KEY (`UID`) ,
  UNIQUE INDEX `username_UNIQUE` (`username` ASC) ,
  INDEX `verified_INDEX` (`verified` ASC) )
ENGINE = InnoDB
DEFAULT CHARACTER SET = utf8;


-- -----------------------------------------------------
-- Table `companies`
-- -----------------------------------------------------
CREATE TABLE `companies` (
  `CID` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
  `name` VARCHAR(45) NOT NULL ,
  `address` VARCHAR(100) NULL ,
  `email` VARCHAR(255) NULL ,
  `phone` VARCHAR(30) NULL ,
  `link` TEXT NULL ,
  `image_small` TEXT NULL ,
  `image_large` TEXT NULL ,
  `yahoo` VARCHAR(100) NULL ,
  `linkin` VARCHAR(100) NULL ,
  `twitter` VARCHAR(20) NULL ,
  `description` TEXT NULL ,
  `shoutout` VARCHAR(140) NULL ,
  `verified` BIT NOT NULL DEFAULT 0 ,
  PRIMARY KEY (`CID`) ,
  INDEX `name_INDEX` (`name` ASC) ,
  INDEX `verified_INDEX` (`verified` ASC) )
ENGINE = InnoDB
DEFAULT CHARACTER SET = utf8;

-- -----------------------------------------------------
-- Table `products`
-- -----------------------------------------------------
CREATE TABLE `products` (
  `PID` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
  `CID` INT UNSIGNED NOT NULL ,
  `name` VARCHAR(100) NULL ,
  `description` TEXT NULL ,
  `image_small` TEXT NULL ,
  `image_large` TEXT NULL ,
  `tag` VARCHAR(45) NULL ,
  `price` DECIMAL(11,2) NULL ,
  PRIMARY KEY (`PID`) ,
  INDEX `tag_INDEX` (`tag` ASC) ,
  INDEX `company.cid_FK` (`CID` ASC) ,
  CONSTRAINT `company.cid_FK`
    FOREIGN KEY (`CID` )
    REFERENCES `companies` (`CID` )
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB
DEFAULT CHARACTER SET = utf8;

-- -----------------------------------------------------
-- Table `users_companies`
-- -----------------------------------------------------
CREATE TABLE `users_companies` (
  `UID` INT UNSIGNED NOT NULL ,
  `CID` INT UNSIGNED NOT NULL ,
  `role` INT UNSIGNED NULL ,
  PRIMARY KEY (`CID`, `UID`) ,
  INDEX `users.uid_FK` (`UID` ASC) ,
  INDEX `company.cid_FK` (`CID` ASC) ,
  CONSTRAINT `users.uid_FK`
    FOREIGN KEY (`UID` )
    REFERENCES `users` (`UID` )
    ON DELETE NO ACTION
    ON UPDATE NO ACTION,
  CONSTRAINT `company.cid_FK`
    FOREIGN KEY (`CID` )
    REFERENCES `companies` (`CID` )
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB
DEFAULT CHARACTER SET = utf8;

나는 오류가있다

누구든지 어느 것이 문제인지 말해 줄 수 있습니까?

 

해결 방법

 

company.cid_FK 라는 두 가지 제약 조건이 있습니다. 이름을 바꿉니다.

 

참조 페이지 https://stackoverflow.com/questions/3316410