MariaDB 10.6

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create table citycitystuff (
  colA varchar(10), 
  colB varchar(10), 
  colC varchar(20)
  );
insert into citycitystuff values 
('CityA', 'CityB', 'Other Stuff'),
('CityA', 'CityC', 'Other Stuff'),
('CityB', 'CityC', 'Other Stuff'),
('CityB', 'CityA', 'Other Stuff'),
('CityB', 'CityA', 'Other Stuff'),
('CityC', 'CityA', 'Other Stuff'),
('CityC', 'CityA', 'Other Stuff'),
('CityC', 'CityB', 'Other Stuff'),
('CityC', 'CityD', 'Other Stuff'),
('CityC', 'CityE', 'Other Stuff'),
('CityC', 'CityE', 'Other Stuff');

Records: 11  Duplicates: 0  Warnings: 0


select 
  colA, 
  colB, 
  colC, 
  count(*) over (partition by colA, colB) as totalEach
from citycitystuff
where colA = 'CityC'


colA
colB
colC
totalEach


CityC
CityA
Other Stuff
2

CityC
CityA
Other Stuff
2

CityC
CityB
Other Stuff
1

CityC
CityD
Other Stuff
1

CityC
CityE
Other Stuff
2

CityC
CityE
Other Stuff
2

colA	colB	colC	totalEach
CityC	CityA	Other Stuff	2
CityC	CityA	Other Stuff	2
CityC	CityB	Other Stuff	1
CityC	CityD	Other Stuff	1
CityC	CityE	Other Stuff	2
CityC	CityE	Other Stuff	2