Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Function CAST (alias my_literal) (children 1)
      ExpressionList (children 2)
       Literal \'1\'
       Literal \'Nullable(UInt64)\'
    ExpressionList (children 1)
     Function plus (children 1)
      ExpressionList (children 2)
       Function sum (children 1)
        ExpressionList (children 1)
         Identifier number
       Function multiply (children 1)
        ExpressionList (children 2)
         Identifier my_literal
         Function count (children 1)
          ExpressionList
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       Function numbers (children 1)
        ExpressionList (children 1)
         Literal UInt64_0
