Upgrading from 1.1.x would make uri fields have length=255

plugins/ActivityModeration/classes/Deleted_notice.php

@@ -193,6 +193,7 @@ class Deleted_notice extends Managed_DataObject
             echo "\nFound old $table table, upgrading it to add 'act_created' field...";
 
             $schemadef['fields']['act_created'] = array('type' => 'datetime', 'not null' => true, 'description' => 'datetime the notice record was created');
+            $schemadef['fields']['uri']['length'] = 191;    // we likely don't have to discover too long keys here
             $schema->ensureTable($table, $schemadef);
 
             $deleted = new Deleted_notice();

plugins/Event/classes/RSVP.php

@@ -107,6 +107,7 @@ class RSVP extends Managed_DataObject
         echo "\nFound old $table table, upgrading it to add 'event_uri' field...";
 
         $schemadef['fields']['event_uri'] = array('type' => 'varchar', 'length' => 191, 'not null' => true, 'description' => 'Event URI');
+        $schemadef['fields']['uri']['length'] = 191;    // we likely don't have to discover too long keys here
         $schema->ensureTable($table, $schemadef);
 
         $rsvp = new RSVP();