[ic] Shared Tables Not Always in %Sql

[John Young]

Mike Heins wrote:
> Quoting John Young (john_young at sonic.net):
> 
>>I'm chasing down an intermittent problem accessing database handles
>>using %Sql (sometimes the table is shared, and sometimes it isn't),
>>and am wondering if the following would be desirable:
>>
>>(I lengthened the diff in order to show the entire block)
>>
>>
>>--- Interpolate.pm.2.201	Wed Jan 14 03:05:29 2004
>>+++ Interpolate.pm	Wed Jan 14 03:11:07 2004
>>@@ -1842,26 +1842,26 @@
>> 	if($tables) {
>> 		my (@tab) = grep /\S/, split /\s+/, $tables;
>> 		foreach my $tab (@tab) {
>>-			next if $Db{$tab};
>>+			next if $Sql{$tab} && $Db{$tab};
>> 			my $db = database_exists_ref($tab);
>> 			next unless $db;
>> 			$db = $db->ref();
>>			if($db->config('type') == 10) {
>>				my @extra_tabs = $db->_shared_databases();
>>				push (@tab, @extra_tabs);
>>			}
>>			if($hole) {
>>				$Sql{$tab} = $hole->wrap($db->dbh())
>>					if $db->can('dbh');
>>				$Db{$tab} = $hole->wrap($db);
>>				if($db->config('name') ne $tab) {
>>					$Db{$db->config('name')} = $Db{$tab};
>>				}
>>			}
>>			else {
>>				$Sql{$tab} = $db->[$Vend::Table::DBI::DBI]
>>					if $db =~ /::DBI/;
>>				$Db{$tab} = $db;
>>			}
>>		}
>>	}
>>
> 
> 
> Does this solve the "Cannot find object method st via package DBD::Pg"
> problem? If it does, then it assuredly would be desirable. 8-)


I don't know... perhaps if $Sql{tablename} is being deleted/undefined
while whomever is using it thinks it is still defined...  Since I don't
have Postgres installed, I hope someone else can test for that.  I don't
recall having seen that error with the DBD I use, nor do I see anything
for it in the archives or Usenet.

The problem I faced was *occasionally* having this scenario fail:

   [perl tables="tablename"]
       ...
       my $dbh = $Sql{tablename} or do ...
       ...
   [/perl]

I speculated that sometimes $Db{tablename} was being defined or retained
while $Sql{tablename} was not... and the existing Interpolate.pm logic
seemed to avoid defining $Sql{tablename} if $Db{tablename} was currently
defined.  To test by forcing the condition, at the beginning of a page
containing the scenario above, I added:

   [perl tables="gift_certs"]
       # This is a test to force existence of $Db and no $Sql.
       my $db = $Db{tablename};
       delete $Sql{tablename};
       return;
   [/perl]
   ... HTML, ITL, etc. ...
   (then the [perl] shown above using my $dbh = $Sql{})

The minor patch above for Interpolate.pm seems to have fixed it in my
limited testing.


Thanks,
John Young