MySQL 5.7

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select version();

version()

5.7.39

CREATE TABLE address(ID INT PRIMARY KEY);

CREATE TABLE resource(ID INT, address_id INT,
constraint foreign key fk_res_to_addr(address_id) REFERENCES address(ID));
SHOW CREATE TABLE resource;

Table
Create Table

resource
CREATE TABLE `resource` (
  `ID` int(11) DEFAULT NULL,
  `address_id` int(11) DEFAULT NULL,
  KEY `fk_res_to_addr` (`address_id`),
  CONSTRAINT `resource_ibfk_1` FOREIGN KEY (`address_id`) REFERENCES `address` (`ID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1

ALTER TABLE resource drop foreign key fk_res_to_addr;

Can't DROP 'fk_res_to_addr'; check that column/key exists

ALTER TABLE resource drop column address_id;

Cannot drop index 'fk_res_to_addr': needed in a foreign key constraint

SHOW CREATE TABLE resource;

Table
Create Table

resource
CREATE TABLE `resource` (
  `ID` int(11) DEFAULT NULL,
  `address_id` int(11) DEFAULT NULL,
  KEY `fk_res_to_addr` (`address_id`),
  CONSTRAINT `resource_ibfk_1` FOREIGN KEY (`address_id`) REFERENCES `address` (`ID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1