I'm doing a series of database queries, which caches the statement handles. Usually this works fine and makes life good, but sometimes, the queries vary as I loop over the following code, and eventually I have memory problems. Then, things go bad (aka crash!). 
  if (my $sth = $self->{$dbh}{$query}) {                              
+                                                                
    warn "Using cached statement handler\n" if $self->debug;          
+                                                                
    return $sth;                                                      
+                                                                
  } else {                                                            
+                                                                
    warn "Creating new statement handler\n" if $self->debug;          
+                                                                
    $sth = $dbh->prepare($query) || $self->throw("Couldn't prepare que
+ry $query:\n ".DBI->errstr."\n");                               
    return $self->{$dbh}{$query} = $sth;                              
+                                                                
  }

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I'd be interested in limiting the number of cached statement handlers, as the caching is only really worthwhile when I am not constantly making new ones. Does anyone have a suggestion on how I could go about this?

I was considering some sort of size limited tied hash, and then shifting an element off, but was looking at what others might suggest.

In reply to how to limit size of hash by albert

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