PostgreSQLの複数の数式

SQLFiddle

select
  2.5*((r-i)/(r+(6*i)-(7.5*n)+1)) as tera,
  (r-(2*i)-n)/(r+(2*i)-n) as tera2
from
  (
  select
    sum(case when wavelength between 340 and 345 then reflectance end) as r,
    sum(case when wavelength between 350 and 355 then reflectance end) as i,
    sum(case when wavelength between 360 and 365 then reflectance end) as n
  from
    test
  ) vars

複数のテーブルの場合、次のようなものを使用できます：

select
  table_name,
  2.5*((r-i)/(r+(6*i)-(7.5*n)+1)) as tera,
  (r-(2*i)-n)/(r+(2*i)-n) as tera2
from
  (
  select
    table_name,
    sum(case when wavelength between 340 and 345 then reflectance end) as r,
    sum(case when wavelength between 350 and 355 then reflectance end) as i,
    sum(case when wavelength between 360 and 365 then reflectance end) as n
  from
    (
      select 'table 1' as table_name, * from test
      union all
      select 'table 2', * from test
      union all
      select 'table 3', * from test      
      union all
      select 'table 4', * from test  
    ) as all_tables
  group by
    table_name
  ) vars

SQLFiddle

テーブル名を実際の名前に変更し、union allを繰り返すだけです。 必要な回数だけ。