It seems a known issue of Management Studio:
- https://social.msdn.microsoft.com/Forums/sqlserver/en-US/255ad3c3-5cb2-4a1a-ad67-099253ee0cb4
- https://social.msdn.microsoft.com/Forums/en-US/29cafaa1-4f41-4ad0-ad00-5990877947f2
As a workaround, try casting to decimal type in your output statements, or use FORMAT:
declare @lat1 float = 52.1234567
declare @lat2 decimal(38,7) = 52.1234567
select @lat1 -- '52,1234567'
select @lat2 -- '52.1234567'
select cast(@lat1 as decimal(38,7)) -- '52.1234567'
DECLARE @latitude VARCHAR(50) = '52.1234567';
DECLARE @longitude VARCHAR(50) = '4.61234567';
SELECT geography::Point(@latitude, @longitude, 4326).Lat -- '52,1234567'
SELECT cast(geography::Point(@latitude, @longitude, 4326).Lat as decimal(38,7)) -- '52.1234567'
SELECT format(geography::Point(@latitude, @longitude, 4326).Lat, 'G') -- '52.1234567'