Using variables to manage what query should be load

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1

Hi all.
Is there any way in MetaBase to use FieldFielter variables to make conditions for selects?

I want to do something like this:

If {{Customer}} = 'Customer_1' Then

  Select field1, field2 
  From Table_A 
  Where {{Customer}}

Else

 Select field5, field, 6, field8 
 From Table_5
  Union All
 Select field5, field, 6, field8 
 From Table_10

End If