Re: Getting more info from a query when exception is thrown

[Andrus Adamchik]

Well, yeah, the query is translated at the lower level of the stack,  
so the generated SQL is not available from the query object directly.  
You can probably intercept the generated SQL by wrapping DataSource/ 
Connection/PreparedStatement. Or maybe use Log4J API with a custom  
Log4J appender for the QueryLogger logger. SQLException may or may  
not contain the info you are looking for - worse checking of course.

Andrus

On Aug 18, 2006, at 8:04 AM, Andreas Pardeike wrote:
Hi,

I am trying to set up an error page in my web application that  
sends error
details to me. I can easily get the stack trace and other variables  
but
I can't the heck find out how to get the last query cayenne has  
executed.

So far, I have managed to set up a DataContextDelegate that is  
called for
every query but I cannot get it to store some valuable info from  
the current
query.

What I want is to retrieve similar information as to what the  
QueryLogger
writes into the log.

INFO  QueryLogger: SELECT t0.SOMPR1, t0.SOMPR2, t0.SOM .. [bind....]

Is that possible?

Or is there an even easier way to retrieve information about the  
querie
at the place where the SQLException is thrown by accessing the  
exception
itself?

Thanks,
Andreas Pardeike



Here's my DataContextDelegate code in my global application object:

dataContext = DataContext.createDataContext();
dataContextDelegate = new DataContextDelegate()
{
  public void finishedMergeChanges(DataObject object) {}
  public void finishedProcessDelete(DataObject object) {}
  public boolean shouldProcessDelete(DataObject object) { return  
true; }
  public boolean shouldMergeChanges(DataObject object, DataRow  
snapshotInStore) { return true; }

  private void store(String type, DataContext c, Query q)
  {
    // TODO - get and store info about the current query
    //        so it can be fetched later at the exception  
displaying page
  }

  public org.objectstyle.cayenne.query.GenericSelectQuery  
willPerformSelect(DataContext context,  
org.objectstyle.cayenne.query.GenericSelectQuery query)
  {
    store("GenericSelectQuery", context, query);
    lastQuery = query;
    return query;
  }

  public Query willPerformQuery(DataContext context, Query query)
  {
    store("Query", context, query);
    lastQuery = query;
    return query;
  }

  public Query willPerformGenericQuery(DataContext context, Query  
query)
  {
    store("GenericQuery", context, query);
    lastQuery = query;
    return query;
  }
};

dataContext.setDelegate(dataContextDelegate);