Explain EXPLAIN (children 2)
 Set
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 2)
    ExpressionList (children 1)
     Subquery (children 1)
      SelectWithUnionQuery (children 1)
       ExpressionList (children 1)
        SelectQuery (children 3)
         ExpressionList (children 1)
          Function count (children 1)
           ExpressionList
         TablesInSelectQuery (children 1)
          TablesInSelectQueryElement (children 1)
           TableExpression (children 1)
            Function numbers (children 1)
             ExpressionList (children 1)
              Literal UInt64_10
         Function equals (children 1)
          ExpressionList (children 2)
           Identifier number
           Identifier n.number
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       Function numbers (alias n) (children 1)
        ExpressionList (children 1)
         Literal UInt64_10
