SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 2)
    Identifier table
    Identifier engine
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.dropped_tables
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier database
     Function currentDatabase (children 1)
      ExpressionList
   Literal UInt64_1
