What's wrong, help please.

Dan Gudmundsson <>
Tue Sep 14 07:52:38 CEST 1999


Try starting mnemosyne first. 
application:start(mnemosyne).

The reason is that simple queries don't need the application 
to be started, while more complex, in this case 2 tables, 
queries requires mnemosyne.

/Dan


 writes:
 > 
 > Then I was trying to execute a mnesia query, based on two tables,
 > such as from eva/examples/simple_adaptation.erl :
 > 
 >     Handle = query [{A.name, A.sender, A.cause, A.severity, AlarmDef.class} ||
 > 			A <- table(alarm),
 > 			AlarmDef <- table(alarmTable),
 > 			A.name = AlarmDef.name] end,
 >     {atomic, Alarms} = mnesia:transaction(fun() -> mnemosyne:eval(Handle) end),
 > 		     ...
 > 
 > I had always got error, such as :
 > {'EXIT',{badarg,{ets,lookup,[db_get,[mnemosyne_catalog,{image,alarm}]]}}} ?
 > 
 > Query, based on one table, executed well.
 > 
 > My environment are RedHat Linux6.0 and Erlang47.4.1 installed from rpm distribution.
 > 
 > Regards.
 > ---
 > Vladimir Sekissov			



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