sql - How to select sum of values in a given range from huge tables quickly (Derby) -

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i got , b table like:

table a

a   b   mount a0  b0  0.0001 a0  b1  0.0002

table b

c   d   weight c0  d0  0.99998 c0  d1  0.99996

each table has 10,000 - 100000 records.

i want combination mount+weight >= 0.9998 , mount+weight <= 0.9999, example:

a   b   c   d    sum a0  b0  c0  d0   0.9999 a0  b1  c0  d1   0.9998

but if takes lot of time when try these ways:

method 1

select b c d mount+weight a,b  mount+weight >= 0.9998 , mount+weight <= 0.9999

a table have index of mount, b table have index of weight

method 2

create a+b table, takes more time method 1.

is there ways improve?

try

select a, b, c, d, mount+weight mw a,b  mount+weight between 0.9998 , 0.9999

this may produce different execution plan

edit: realised derby. not sure if between available in derby


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