sql - Better way to write a query -


i'm creating view after joining table , view. view contains actual columns in join , of them calculated columns(lets call them type1). of them calculations of calculated columns (type2). there way can reference type1 columns calculate type2 names instead of writing entire code again? ( don't want create subquery either), checking if there efficient way write code. not posting actual code here ,this short form of i'm trying do:

    create view abcd       col1,col2 , calc_col1, calc_col2 , calc_col3          select a.col1 col1 ,             a.col2 col2,             case when  some_calulations 2 else 0  end calc_col1,            ( case when  some_calulations 2 else 0  end) - a.somecol calc_col2 ,       ( ( case when  some_calulations 2 else 0  end) - a.somecol ) + 5 )as calc_col3   table1    left join view2 b    on join_condition

use lateral subqueries

select     a.col1 col1,     a.col2 col2,     c.calc_col1,     d.calc_col2,     d.calc_col2 + 5 calc_col3      table1     left join     view2 b on join_condition     cross join lateral     (select case when some_calulations 2 else 0 end calc_col1) c     cross join lateral     (select calc_col1 - a.somecol calc_col2) d

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