[ci skip] Don't try to insert_batch() when we know it's not supported on Firebird
diff --git a/system/database/drivers/ibase/ibase_driver.php b/system/database/drivers/ibase/ibase_driver.php
index c1055c1..671a353 100644
--- a/system/database/drivers/ibase/ibase_driver.php
+++ b/system/database/drivers/ibase/ibase_driver.php
@@ -384,6 +384,23 @@
 	// --------------------------------------------------------------------
 
 	/**
+	 * Insert batch statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data.
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return	string|bool
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Close DB Connection
 	 *
 	 * @return	void
diff --git a/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
index 96dcc5e..7811d3d 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
@@ -260,4 +260,20 @@
 		return preg_replace('`SELECT`i', 'SELECT '.$select, $sql);
 	}
 
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert batch statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data.
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return	string|bool
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+	}
 }
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 2c8a131..d99e442 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -26,6 +26,7 @@
 -  Fixed a bug (#4787) - :doc:`Form Validation Library <libraries/form_validation>` method ``valid_email()`` triggered ``E_WARNING`` when input emails have empty domain names.
 -  Fixed a bug (#4805) - :doc:`Database <database/index>` driver 'mysqli' didn't use the ``MYSQLI_CLIENT_SSL_DONT_VERIFY_SERVER_CERT`` flag properly.
 -  Fixed a bug (#4808) - :doc:`Database <database/index>` method ``is_write_type()`` only looked at the first line of a queries using ``RETURNING`` with the 'postgre', 'pdo/pgsql', 'odbc' and 'pdo/odbc' drivers.
+-  Fixed a bug where :doc:`Query Builder <database/query_builder>` method ``insert_batch()`` tried to execute an unsupported SQL query with the 'ibase' and 'pdo/firebird' drivers.
 
 Version 3.1.0
 =============