CREATE SCHEMA `test` DEFAULT CHARACTER SET utf8 ;
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CREATE  TABLE `test`.`testutf8mb4` (
  `testValue` VARCHAR(50) NOT NULL ,
  PRIMARY KEY (`testValue`) );
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USE `test`;
DROP procedure IF EXISTS `testRecord`;

DELIMITER $$
USE `test`$$
CREATE PROCEDURE `testRecord`(
    _testValue VARCHAR(50)
)
BEGIN
IF EXISTS (select 1 from `test`.`testutf8mb4` where testValue = _testValue)
THEN 
select CONCAT('testValue: ', _testValue, ' already exists.');
ELSE INSERT INTO `test`.`testutf8mb4` (
        `testValue`
    ) VALUES (
        _testValue
    );
select CONCAT('testValue: ', _testValue, ' Record added.');
END IF;
END
$$

DELIMITER ;
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call test.testRecord('Сарнаут✔𝐖✪𝐅✔М');
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select * from test.testutf8mb4;