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 isNull (children 1)
     ExpressionList (children 1)
      Function dictGetOrNull (children 1)
       ExpressionList (children 3)
        Literal \'dictionary_all\'
        Literal \'name\'
        Identifier id
    ExpressionList (children 2)
     OrderByElement (children 1)
      Identifier id
     OrderByElement (children 1)
      Identifier payload
