diff --git a/docs/topics/logging.txt b/docs/topics/logging.txt
index 309ea364b4..d5219872ef 100644
--- a/docs/topics/logging.txt
+++ b/docs/topics/logging.txt
@@ -458,6 +458,10 @@ Messages to this logger have the following extra context:
     * ``sql``: The SQL statement that was executed.
     * ``params``: The parameters that were used in the SQL call.
 
+For performance reasons, SQL logging is only occurs when
+``settings.DEBUG`` is set to ``True``, regardless of the logging
+level or handlers that are installed.
+
 .. note::
     Due to a limitation in the logging library, this extra
     context is not available if you are using Python 2.4.