diff --git a/includes/common.inc b/includes/common.inc
index 26282bf5b1a..e110e517aa9 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -729,6 +729,8 @@ function _drupal_exception_handler($exception) {
  * @return An error in the format expected by _drupal_log_error().
  */
 function _drupal_decode_exception($exception) {
+  $message = $exception->getMessage();
+
   $backtrace = $exception->getTrace();
   // Add the line throwing the exception to the backtrace.
   array_unshift($backtrace, array('line' => $exception->getLine(), 'file' => $exception->getFile()));
@@ -741,17 +743,20 @@ function _drupal_decode_exception($exception) {
     // or in one of its global functions.
     $db_functions = array('db_query', 'pager_query', 'db_query_range', 'db_query_temporary', 'update_sql');
     while (!empty($backtrace[1]) && ($caller = $backtrace[1]) &&
-        ((isset($caller['class']) && (strpos($caller['class'], 'Query') !== FALSE || strpos($caller['class'], 'Database') !== FALSE)) ||
+        ((isset($caller['class']) && (strpos($caller['class'], 'Query') !== FALSE || strpos($caller['class'], 'Database') !== FALSE || $caller['class'] == 'PDOStatement')) ||
         in_array($caller['function'], $db_functions))) {
       // We remove that call.
       array_shift($backtrace);
     }
+    if (isset($exception->query_string, $exception->args)) {
+      $message .= ": " . $exception->query_string . "; " . print_r($exception->args, TRUE);
+    }
   }
   $caller = _drupal_get_last_caller($backtrace);
 
   return array(
     '%type' => get_class($exception),
-    '%message' => $exception->getMessage(),
+    '%message' => $message,
     '%function' => $caller['function'],
     '%file' => $caller['file'],
     '%line' => $caller['line'],
diff --git a/includes/database/database.inc b/includes/database/database.inc
index 60d4b415fae..f1185c77aca 100644
--- a/includes/database/database.inc
+++ b/includes/database/database.inc
@@ -595,13 +595,15 @@ abstract class DatabaseConnection extends PDO {
     catch (PDOException $e) {
       _db_check_install_needed();
       if ($options['throw_exception']) {
+        // Add additional debug information.
         if ($query instanceof DatabaseStatementInterface) {
-          $query_string = $stmt->getQueryString();
+          $e->query_string = $stmt->getQueryString();
         }
         else {
-          $query_string = $query;
+          $e->query_string = $query;
         }
-        throw new PDOException($query_string . " - \n" . print_r($args, 1) . $e->getMessage());
+        $e->args = $args;
+        throw $e;
       }
       return NULL;
     }
diff --git a/includes/database/pgsql/database.inc b/includes/database/pgsql/database.inc
index ba82aa0b0fc..0f5627c2a28 100644
--- a/includes/database/pgsql/database.inc
+++ b/includes/database/pgsql/database.inc
@@ -80,13 +80,15 @@ class DatabaseConnection_pgsql extends DatabaseConnection {
     catch (PDOException $e) {
       _db_check_install_needed();
       if ($options['throw_exception']) {
+        // Add additional debug information.
         if ($query instanceof DatabaseStatementInterface) {
-          $query_string = $stmt->getQueryString();
+          $e->query_string = $stmt->getQueryString();
         }
         else {
-          $query_string = $query;
+          $e->query_string = $query;
         }
-        throw new PDOException($query_string . " - \n" . print_r($args, 1) . $e->getMessage());
+        $e->args = $args;
+        throw $e;
       }
       return NULL;
     }
diff --git a/modules/simpletest/tests/database_test.test b/modules/simpletest/tests/database_test.test
index 0263036ef25..e5d5b3fe0b1 100644
--- a/modules/simpletest/tests/database_test.test
+++ b/modules/simpletest/tests/database_test.test
@@ -2446,6 +2446,9 @@ class DatabaseInvalidDataTestCase extends DatabaseTestCase {
         $this->pass(t('The whole transaction is rolled back when a duplicate key insert occurs.'));
       }
 
+      // 23000 means "Integrity constraint violation" according to ANSI SQL.
+      $this->assertEqual($e->errorInfo[0], '23000', t('Exception has proper SQLSTATE.'));
+
       // Ensure the other values were not inserted.
       $record = db_select('test')
         ->fields('test', array('name', 'age'))
diff --git a/modules/simpletest/tests/error.test b/modules/simpletest/tests/error.test
index 8584e2a40a2..ed430bfff26 100644
--- a/modules/simpletest/tests/error.test
+++ b/modules/simpletest/tests/error.test
@@ -78,7 +78,7 @@ class DrupalErrorHandlerUnitTest extends DrupalWebTestCase {
     );
     $error_pdo_exception = array(
       '%type' => 'PDOException',
-      '%message' => 'SQLSTATE',
+      '%message' => 'SELECT * FROM bananas_are_awesome',
       '%function' => 'error_test_trigger_pdo_exception()',
       '%line' => 65,
       '%file' => realpath('modules/simpletest/tests/error_test.module'),
@@ -89,7 +89,7 @@ class DrupalErrorHandlerUnitTest extends DrupalWebTestCase {
 
     $this->drupalGet('error-test/trigger-pdo-exception');
     // We cannot use assertErrorMessage() since the extact error reported
-    // varies from database to database. Check for the error keyword 'SQLSTATE'.
+    // varies from database to database. Check that the SQL string is displayed.
     $this->assertText($error_pdo_exception['%type'], t('Found %type in error page.', $error_pdo_exception));
     $this->assertText($error_pdo_exception['%message'], t('Found %message in error page.', $error_pdo_exception));
     $error_details = t('in %function (line %line of %file)', $error_pdo_exception);