Explain EXPLAIN SYNTAX (children 2)
 Set
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 4)
    ExpressionList (children 2)
     Identifier id
     Identifier payload
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier tab
    Function equals (children 1)
     ExpressionList (children 2)
      Function dictGetIPv6 (children 1)
       ExpressionList (children 3)
        Literal \'dictionary_all\'
        Literal \'ip6\'
        Identifier id
      Function toIPv6 (children 1)
       ExpressionList (children 1)
        Literal \'2001:db8::1\'
    ExpressionList (children 2)
     OrderByElement (children 1)
      Identifier id
     OrderByElement (children 1)
      Identifier payload
