Geodistance filter, optimize_bbox, indexed


(Pierre Durand) #1

Hi,

What is the use of the "indexed" value for the "optimize_bbox" in the
"geodistance" filter?
It is slower than the "memory" value!

Do you have an explanation?

Thank you


(Shay Banon) #2

When doing geo distance calculation, the actual distance forumla is
expensive. In order to speed it up, a bounding box is built around the
distance, and a check is made first to see if we really need to compute the
distance.

The check by default is done using in memory checks, which is 95% of the
time the way you would want to do it. The indexed option simply uses the
indexed lat and lon to build numeric range filters against them, using the
index to do the bounding box calcs.

On Sun, Jun 24, 2012 at 2:13 AM, Pierre Durand pierredurand@gmail.comwrote:

Hi,

What is the use of the "indexed" value for the "optimize_bbox" in the
"geodistance" filter?
It is slower than the "memory" value!

Do you have an explanation?

Thank you


(Pierre Durand) #3

Ok, thank you :slight_smile:

On Monday, June 25, 2012 2:18:59 PM UTC+2, kimchy wrote:

When doing geo distance calculation, the actual distance forumla is
expensive. In order to speed it up, a bounding box is built around the
distance, and a check is made first to see if we really need to compute the
distance.

The check by default is done using in memory checks, which is 95% of the
time the way you would want to do it. The indexed option simply uses the
indexed lat and lon to build numeric range filters against them, using the
index to do the bounding box calcs.

On Sun, Jun 24, 2012 at 2:13 AM, Pierre Durand pierredurand@gmail.comwrote:

Hi,

What is the use of the "indexed" value for the "optimize_bbox" in the
"geodistance" filter?
It is slower than the "memory" value!

Do you have an explanation?

Thank you


(system) #4