SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Identifier a
    Identifier b
    Identifier c
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier decimal
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier a
     Function toFloat64 (children 1)
      ExpressionList (children 1)
       Literal UInt64_42