mysql - Combining SQL SUM clauses -

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i have script requires executing 4 rather large mysql queries on same subset of data. there way combine them 1 query?

here query looks like: 

select sum(value)      ( select lat, lng, value `pop_geo_199` (          (lat between 38.1768916977 , 39.6131083023) , (lng between -77.9596650363 , -76.1143349637))          ) firstcut  (acos(0.627895140732*sin(radians(lat)) + 0.778297945677*cos(radians(lat))*cos(radians(lng)-(-1.34454929586))) * 6371 < 79.85)

as can tell, geographic query of latitude , longitude points. query first create simple square subset of total table (firstcut), , runs trig functions on circular area.

from can tell, part of query slow firstcut, because table drawing on has 2.8 million rows. firstcut, though, in instance, has 27,922 rows, trig part goes super fast comparison.

the issue is, have run few of these. can use same firstcut, though, since different radii centered on same area. i'd love able pull off 1 query instead of four.

here second query looks like:

select sum(value)      ( select lat, lng, value `pop_geo_199` (          (lat between 38.1768916977 , 39.6131083023) , (lng between -77.9596650363 , -76.1143349637))          ) firstcut  (acos(0.627895140732*sin(radians(lat)) + 0.778297945677*cos(radians(lat))*cos(radians(lng)-(-1.34454929586))) * 6371 < 48.57)

as can see same other 1 except last clause slight different — condition smaller radii (48.57 instead of 79.85).

how can combine these 2 queries 1 query in efficient way?

i've tried using case clauses -- best approach?

select   sum(case when (acos(0.627895140732*sin(radians(lat)) + 0.778297945677*cos(radians(lat))*cos(radians(lng)-(-1.34454929586))) * 6371 < 79.85) value else 0 end),  sum(case when (acos(0.627895140732*sin(radians(lat)) + 0.778297945677*cos(radians(lat))*cos(radians(lng)-(-1.34454929586))) * 6371 < 48.57) value else 0 end)  ( select lat, lng, value `pop_geo_199` ((lat between 38.1768916977 , 39.6131083023) , (lng between -77.9596650363 , -76.1143349637)) ) firstcut;

you can use case statement this. can move calculation subquery:

select       sum(case             when rad < 79.85            value             else 0 end)  1stquerysum,      sum(case             when rad < 48.57             value             else 0 end)  2ndquerysum  (      select lat, lng, value,             acos(0.627895140732*sin(radians(lat)) + 0.778297945677*cos(radians(lat))*cos(radians(lng)-(-1.34454929586))) * 6371 rad     `pop_geo_199`      (          (lat between 38.1768916977 , 39.6131083023) ,           (lng between -77.9596650363 , -76.1143349637)     )  ) firstcut

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