SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function count (children 1)
     ExpressionList (children 1)
      Asterisk
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.processes
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier current_database
     Function currentDatabase (children 1)
      ExpressionList