Module: DWH::Functions::Nulls

Included in:
DWH::Functions
Defined in:
lib/dwh/functions/nulls.rb

Overview

Manages translations to Null handling Functions

Instance Method Summary collapse

Instance Method Details

#if_null(exp, exp_if_null) ⇒ Object

If the provided expression is null then return the second expression.

Parameters:

  • exp (String) —
    • target expression
  • exp_if_null (String) —
    • exp if target is null


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# File 'lib/dwh/functions/nulls.rb', line 9

def if_null(exp, exp_if_null)
  gsk(:if_null)
    .sub(/@exp/i, exp.to_s)
    .sub(/@when_null/i, exp_if_null.to_s)
end

#null_if(exp, target_exp) ⇒ Object

Returns Null if the given expression equals the target expression.



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# File 'lib/dwh/functions/nulls.rb', line 17

def null_if(exp, target_exp)
  gsk(:null_if)
    .sub(/@exp/i, exp.to_s)
    .sub(/@target/i, target_exp.to_s)
end

#null_if_zero(exp) ⇒ Object

Returns Null if the given expression evaluates to zero.



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# File 'lib/dwh/functions/nulls.rb', line 25

def null_if_zero(exp)
  gsk(:null_if_zero)
    .sub(/@exp/i, exp.to_s)
end