doc: Note that plugin authors must NEVER modify tables they don't control

* docs/source/pluginwriter/database.rst: New paragraph.

diff --git a/docs/source/pluginwriter/database.rst b/docs/source/pluginwriter/database.rst
index 2af05f6d39d9a86fbd8a03aa7a0730d2439342e8..c0698a240f3b579ae43e8df4fb48d2d76864abd3 100644 (file)
--- a/docs/source/pluginwriter/database.rst
+++ b/docs/source/pluginwriter/database.rst
@@ -142,4 +142,9 @@ accordingly, and read carefully!  Now you should also test your
 migration with some real data.  Be sure to test it both on sqlite
 *AND* on postgresql!
 
+One last *very critical* note: you must never, never modify core
+tables with your plugin.  To do that is to put you and all your users
+in a dangerous situation.  Add data to the database by adding new tables
+under the control of your plugin, but never ever modify anyone else's!
+
 Whew, you made it!  Get yourself a cookie to celebrate!