MariaDB 10.2

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CREATE TABLE IF NOT EXISTS `accounts` (
  `master_id` int(3) unsigned NOT NULL,
  `child_id` int(3) unsigned NOT NULL,
  `name` varchar(200) NOT NULL
);
INSERT INTO `accounts` (`master_id`, `child_id`, `name`) VALUES
  ('222', '555', 'child_555'),
  ('111', '111', 'master_111'),
  ('111', '999', 'child_999'),
  ('111', '888', 'child_888'),
  ('222', '222', 'master_222'),
  ('222', '777', 'child_777'),
  ('111', '666', 'child_666');
SELECT 
  `master_id`, 
  max(case when `master_id` = `child_id` then `name` end) n,
  count(case when `master_id` != `child_id` then 1 end) as "Total Accounts"
FROM `accounts` a1
GROUP BY master_id ASC;


master_id
n
Total Accounts


111
master_111
3

222
master_222
2