SelectWithUnionQuery (children 3)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 2)
    Function ignore (children 1)
     ExpressionList (children 3)
      Function toFixedString (children 1)
       ExpressionList (children 2)
        Literal \'Lambda as function parameter\'
        Literal UInt64_28
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_28
      Function ignore (children 1)
       ExpressionList (children 1)
        Literal UInt64_8
    Function sum (children 1)
     ExpressionList (children 1)
      Identifier marks
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.parts
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier database
     Function currentDatabase (children 1)
      ExpressionList
   ExpressionList (children 1)
    ExpressionList (children 1)
     Literal UInt64_2
 Identifier Null
 Set
