[postgis-users] Calculation of Radius in PostGIS

[Diego Roberto]

Hello,

I need to generate a calculation of lightning and I'm not getting. I have
the following situation. I have a point with the coordinates -16.675297,
-49.260196 and was stored in the database in spatial format with SRID 4326.
Need to generate a buffer of 100 meters from this point and check which
other points are within this buffer to return to the user.
Realize the following conversion to make this calculation:
http://spatialreference.org/ref/epsg/2163/

SELECT i.id_impediments
FROM THE impediments i
WHERE st_dwithin (transform (i.geometry_data, 2163),
transform (GeomFromText ('POINT (-16.675297 -49.260196)', 4326), 2163),
100)

My questions are:
This is the best way to calculate a buffer and from the moment I work with
the conversion to SRID 2163 SELECT can do this only for the range of
coordinates described in this link:
I believe that this conversion also realize that is not the correct way.
Could help me transferring any material or link so I can study?

I know there's no way I generate a buffer with WGS84 (4326) so I convert to
2163. Working with this?

Thank you.
And I appreciate the attention.

-- 
________________________________________________
Diego Roberto

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