MySQL 5.7

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CREATE TABLE `clients` (
`id` smallint(5) UNSIGNED NOT NULL,
`name` varchar(32) DEFAULT NULL,
`phones` json DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
insert into `clients` values
	(1, 'пользователь 1', '["380990000123"]'),
	(2, 'пользователь 2', '[]'),
	(3, 'пользователь 3', '["380991234567","380958877654", "380958877655"]');
select
    replace(replace(replace(replace(phones,', ',' '),'"',''),'[',''),']','') phones
  from clients;


phones


380990000123



380991234567 380958877654 380958877655