no.089_s00.milm

一个内存数据库的源代码这是服务器端还有客户端

# >Number:         89
include "mil_algebra_procs";
include "mil_insert";
include "mil_system_procs";
# >Category:       Mserver
# >Synopsis:       abort doesn't work right when BATs are unloaded
# >Confidential:   no
# >Severity:       serious
# >Priority:       high
# >Responsible:    boncz
# >State:          open
# >Class:          sw-bug
# >Submitter-Id:   unknown
# >Arrival-Date:   Mon Dec  1 14:49:04 1997
# >Originator:     windhouw
# >Organization:
# UvA
# >Release:        971007
# >Environment:
# 
# >Description:
# The following problem occurs:
# - I'm running a "transaction";
# - I abort the transaction;
# - the updates and inserts seems to be reversed;
# - I quit Mserver and restart it;
# - the updates and inserts are back again.
# 
# It seems to be that BATs that are swapped out of
# memory, don't take part in the abort.
# 
# I replayed this scene by explicitly swapping the BAT
# to disk:
# #You are system administrator (adm)!
# >module(url);
# >Server := new(oid,url);
# >Server.persists(true);
# >Server.rename("Server");
# >Server.insert(oid(1),url("http://www.cwi.nl/")); 
# >Server.print;
# #---------------------------------#
# # oid   | Server                  #
# #---------------------------------#
# [ 1@0,    http://www.cwi.nl/      ]
# >Server.unload;
# >abort;
# >Server.print;
# #-----------------#
# # oid   | Server  #
# #-----------------#
# ... QUIT & RESTART ...
# #You are system administrator (adm)!
# >module(url);
# >Server.print;
# #---------------------------------#
# # oid   | Server                  #
# #---------------------------------#
# [ 1@0,    http://www.cwi.nl/      ]
# 
# As this problem frequently occurs while testing my
# application, my database gets inconsistent which
# leads to runtime errors in the odmg packages (like
# oid not found in the extent), while abort should
# give me the possibilty to get back to the previous
# consistent state of the database.

module(url);
var Server:= new(oid,url).persists(true).rename("Server");
var Server2:= new(oid,url).persists(true).rename("Server2");
var Clients:= new(oid,int).persists(true).rename("Clients");
var Clients2:= new(oid,int).persists(true).rename("Clients2");
commit();
Server.insert(oid(1),url("http://www.cwi.nl/")); 
Server2.insert(oid(1),url("http://www.cwi.nl/")); 
Clients.insert(oid(1),3); 
Clients2.insert(oid(1),3); 
Server.print();
Server2.print();
Clients.print();
Clients2.print();
dir("Server");
dir("Clients");
unload("Server");
unload("Clients");
dir("Server");
dir("Clients");
abort();
dir("Server");
dir("Clients");
Server.print();
Server2.print();
Clients.print();
Clients2.print();
quit();