diff --git a/modules/dblog/dblog.install b/modules/dblog/dblog.install
index abfd9a2..ed27599 100644
--- a/modules/dblog/dblog.install
+++ b/modules/dblog/dblog.install
@@ -51,10 +51,8 @@ function dblog_schema() {
         'description' => 'The severity level of the event; ranges from 0 (Emergency) to 7 (Debug)',
       ),
       'link' => array(
-        'type' => 'varchar',
-        'length' => 255,
+        'type' => 'text',
         'not null' => FALSE,
-        'default' => '',
         'description' => 'Link to view the result of the event.',
       ),
       'location'  => array(
@@ -155,5 +153,17 @@ function dblog_update_7002() {
 }
 
 /**
+ * Convert the link column to text.
+ */
+function dblog_update_7003() {
+  // Allow NULL values for links.
+  db_change_field('watchdog', 'link', 'link', array(
+    'type' => 'text',
+    'not null' => FALSE,
+    'description' => 'Link to view the result of the event.',
+  ));
+}
+
+/**
  * @} End of "addtogroup updates-7.x-extra".
  */
diff --git a/modules/dblog/dblog.module b/modules/dblog/dblog.module
index 9183eed..7579642 100644
--- a/modules/dblog/dblog.module
+++ b/modules/dblog/dblog.module
@@ -147,14 +147,14 @@ function dblog_watchdog(array $log_entry) {
   Database::getConnection('default', 'default')->insert('watchdog')
     ->fields(array(
       'uid' => $log_entry['uid'],
-      'type' => substr($log_entry['type'], 0, 64),
+      'type' => drupal_substr($log_entry['type'], 0, 64),
       'message' => $log_entry['message'],
       'variables' => serialize($log_entry['variables']),
       'severity' => $log_entry['severity'],
-      'link' => substr($log_entry['link'], 0, 255),
+      'link' => $log_entry['link'],
       'location' => $log_entry['request_uri'],
       'referer' => $log_entry['referer'],
-      'hostname' => substr($log_entry['ip'], 0, 128),
+      'hostname' => drupal_substr($log_entry['ip'], 0, 128),
       'timestamp' => $log_entry['timestamp'],
     ))
     ->execute();
diff --git a/modules/dblog/dblog.test b/modules/dblog/dblog.test
index bf409c9..03308af 100644
--- a/modules/dblog/dblog.test
+++ b/modules/dblog/dblog.test
@@ -119,13 +119,16 @@ class DBLogTestCase extends DrupalWebTestCase {
   private function generateLogEntries($count, $type = 'custom', $severity = WATCHDOG_NOTICE) {
     global $base_root;
 
+    // Make it just a little bit harder to pass the link part of the test.
+    $link = urldecode('/content/xo%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A%E9%85%B1%E5%87%89%E6%8B%8C%E7%B4%A0%E9%B8%A1%E7%85%A7%E7%83%A7%E9%B8%A1%E9%BB%84%E7%8E%AB%E7%91%B0-%E7%A7%91%E5%B7%9E%E7%9A%84%E5%B0%8F%E4%B9%9D%E5%AF%A8%E6%B2%9F%E7%BB%9D%E7%BE%8E%E9%AB%98%E5%B1%B1%E6%B9%96%E6%B3%8A-lake-isabelle');
+
     // Prepare the fields to be logged
     $log = array(
       'type'        => $type,
       'message'     => 'Log entry added to test the dblog row limit.',
       'variables'   => array(),
       'severity'    => $severity,
-      'link'        => NULL,
+      'link'        => $link,
       'user'        => $this->big_user,
       'uid'         => isset($this->big_user->uid) ? $this->big_user->uid : 0,
       'request_uri' => $base_root . request_uri(),
@@ -634,4 +637,3 @@ class DBLogTestCase extends DrupalWebTestCase {
     $this->assertLink(html_entity_decode($message_text), 0, $message);
   }
 }
-