MySQL 5.7

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create table Empl (id int primary key, firstname varchar(8), lastname varchar(8))
insert into Empl values (1, 'fname1', 'lname')
insert into Empl values (2, 'fname2', 'lname')
select * from Empl GROUP BY LastName HAVING COUNT(LastName) >1
Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'db_2087464120.Empl.id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by