[postgis-users] ST_Buffer questions

[Chen, Li [Contractor]]

Hi Everyone,
I am a newbie to this community and I would like to ask a question/s :).

Q1.
ST_Buffer(g1, range) is able to return a geometry within the range of g1.

So, I define two point using lon/lat (SRID=4326) and range 10km. I want to see whether they cross each other by using ST_Crosses(g1, g2).
However, I don't know the unit of the range parameter in ST_Buffer(g1,range)  as it is not provide in the docs. So is it km or meters?

Q2.
I want to define many circle sectors around the earth. And I have a column to set the location of the centre and another column to set the shape of the sector (direction, diameter). Is there a function to return a geometry that represents both the location and shape of the sector? ST_Buffer only returns a full circle.

Thanks for the help,

Li
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