SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 2)
    Identifier name
    Function caseWithExpression (alias result) (children 1)
     ExpressionList (children 6)
      Identifier name
      Function substring (children 1)
       ExpressionList (children 3)
        Identifier name
        Literal UInt64_1
        Literal UInt64_1
      Literal \'First letter\'
      Function reverse (children 1)
       ExpressionList (children 1)
        Identifier name
      Literal \'Reversed match\'
      Literal \'No Match\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Function arrayJoin (alias name) (children 1)
            ExpressionList (children 1)
             Literal Array_[\'Alice\', \'Bob\', \'Charlie\', \'David\', \'abba\', \'A\']
