DatabaseConnection_oracle->readBlob()

you have to migrate the blobs table... or you may lose data

this is probably because you use db caching.. cache_* tables...

try to:

begin
   for c_cur in (select table_name from user_tables where table_name like 'CACHE_%') loop
      execute immediate 'truncate table '||c_cur.table_name;
   end loop; 
end;

this should solve your problem. remeber to reschedule the blob cleanup job from admin/settings/oracle/blob screen.

have you got some error in your apache error logs?

yes it is, i've understood that you can't access this page.

I'm still getting this error:

Notice: Trying to get property of non-object in DatabaseConnection_oracle->readBlob() (line 564 of /web/shared/drupal/includes/database/oracle/database.inc).

Drupal was installed from the start to the Oracle DB. I was able to investigate, that at some point Drupal driver does not convert data to proper datatype or what it expects.

For example it looks for object but gets array, or other inconsistencies. Using version = "7.x-1.9" of Oracle module. Drupal 7.8.

Any update on this?

Managed to get rid of that notice messages like this:

public function readBlob($handle) {
	// can we have a try/catch please?
	try {
		$handle = (int) substr($handle,strlen(ORACLE_BLOB_PREFIX));
		$stmt = parent::prepare("select content from blobs where blobid= ?");
		$stmt->bindParam(1, $handle, PDO::PARAM_INT, 32);
		$stmt->execute();

		// do we really have an object?
		return is_object($obj = $stmt->fetchObject()) ? $obj->content : '';

		//return $stmt->fetchObject()->content;
	} catch(PDOException $c) {
		watchdog('Oracle readBlob exception', '<pre>'.print_r($c->getMessage(), true).'</pre>');
		return '';
	}
}

The main reason for it was, that there were no blob by handle ID and it failed to check.

D7 reached its EOL back in January 2025, and there is no active release for D7 for this module anymore.
Development or support is not planned for D7. All D7-related issues are marked as outdated in a bunch.

Everyone can apply the patches/suggestions above (not tested by the maintainers, tested by the community) to their D7 projects.
If the issue remains relevant for D10+ versions, merge requests with proposed solutions for a new module version (D10+) are welcome in a new follow-up issue.

Thanks!