SQL地理字符串解析

Question

为什么这有效，

select geography::STGeomFromText('POINT(-77.010996 38.890358)',4326)

但这不起作用

declare @Latitude decimal(9,6) = 38.890358  
declare @Longitude decimal(9,6) = -77.010996

select geography::STGeomFromText('''POINT(' + 
cast(@Longitude as nvarchar(15)) + ' ' + 
cast(@Latitude as nvarchar(15)) +')''',4326)

我错过了什么，它们似乎实际上是同一件事。

Answer 1

去掉开头和结尾的多余引号

declare @Latitude decimal(9,6) = 38.890358  
declare @Longitude decimal(9,6) = -77.010996

select geography::STGeomFromText('POINT(' + 
cast(@Longitude as nvarchar(15)) + ' ' + 
cast(@Latitude as nvarchar(15)) +')',4326)