[postgis-users] Nearest line from a point

[Stephen Woodbridge]

On 8/20/2011 3:34 PM, Jaime Casanova wrote:
> On Sat, Aug 20, 2011 at 7:36 AM, Charles Galpin<cgalpin at lhsw.com>  wrote:
>> I assume you mean it takes a long time? The key is to create a buffer around the point that is as big as you feel necessary to make a
>> match, and then in your where clause only match lines that intersect this. That way the index is used to limit the number of
>> candidates to get the distance for.  Something like
>>
>> where line&&  st_expand(myPoint, bufferSizeInYourProjectionUnits)
>>
>
> st_dwithin() doesn't do this automatically?
> but i should admit it wasn't useful for me... it still require a seq
> scan on the whole table
>

Have you create a gist (not a btree) index on your geometry column?

-Steve