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CREATE TABLE `brand` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`name` varchar(512) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
CREATE TABLE `product` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL,
`ean_code` varchar(255) DEFAULT NULL,
`brand_id` bigint(20) DEFAULT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `product_eancode_unique` (`brand_id`,`ean_code`),
CONSTRAINT `fk_product_brand_id` FOREIGN KEY (`brand_id`) REFERENCES `brand` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
ALTER TABLE product drop column `ean_code`;
Key column 'ean_code' doesn't exist in table
alter table `product` drop key `product_eancode_unique`, drop column `ean_code`;
Cannot drop index 'product_eancode_unique': needed in a foreign key constraint