MySQL 8.0

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CREATE TABLE app_log (
  `LOG_ID` INTEGER,
  `APP_NAME` VARCHAR(5),
  `ERROR-MESSAGE` VARCHAR(34),
  `ERROR-DATE` VARCHAR(10)
);

INSERT INTO app_log
  (`LOG_ID`, `APP_NAME`, `ERROR-MESSAGE`, `ERROR-DATE`)
VALUES
  ('1', 'APP_1', 'UNABLE TO CONNECT -  101', '2021-03-14'),
  ('2', 'APP_1', 'UNABLE TO CONNECT - 101', '2021-03-01'),
  ('3', 'APP_1', 'UNABLE TO CONNECT - 101', '2021-01-01'),
  ('4', 'APP_1', 'UNABLE TO CONNECT - 102', '2021-03-14'),
  ('5', 'APP_1', 'UNABLE TO CONNECT - 102', '2021-01-01'),
  ('6', 'APP_1', 'UNABLE TO CONNECT - SERVER ERROR', '2021-03-14'),
  ('7', 'APP_1', 'UNABLE TOCONNECT -102', '2020-01-01'),
  ('8', 'APP_2', 'SERVER ERROR 1', '2021-03-14'),
  ('9', 'APP_2', 'SERVER ERROR 1', '2021-03-01'),
  ('10', 'APP_2', 'SERVER ERROR 1', '2021-01-01'),
  ('11', 'APP_2', 'SERVER ERROR 2', '2021-03-14'),
  ('12', 'APP_2', 'SERVER ERROR 2', '2020-01-01'),
  ('13', 'APP_2', 'PROXY ERROR', '2021-03-14'),
  ('14', 'APP_3', 'SERVER UNAVAILABLE', '2021-03-14'),
  ('15', 'APP_3', 'SERVER UNAVAILABLE', '2021-03-01'),
  ('16', 'APP_3', 'SERVER UNAVAILABLE', '2021-01-01');

MAX(LOG_ID)	APP_NAME	ERROR-MESSAGE	MAX(`ERROR-DATE`)	count_messages
9	APP_2	SERVER ERROR 1	2021-03-14	2
15	APP_3	SERVER UNAVAILABLE	2021-03-14	2
1	APP_1	UNABLE TO CONNECT - 101	2021-03-14	1
2	APP_1	UNABLE TO CONNECT - 101	2021-03-01	1
4	APP_1	UNABLE TO CONNECT - 102	2021-03-14	1
6	APP_1	UNABLE TO CONNECT - SERVER ERROR	2021-03-14	1
11	APP_2	SERVER ERROR 2	2021-03-14	1
13	APP_2	PROXY ERROR	2021-03-14	1