MDL-38972 add upgrade info for duplicate index-key problems

2013-04-18 20:21:03 +02:00
parent 02e5f81c94
commit 2d97513d12
1 changed files with 2 additions and 0 deletions
@@ -65,6 +65,8 @@ information provided here is intended especially for developers.
 Database (DML) layer:
 * $DB->sql_empty() is deprecated, you have to use sql parameters with empty values instead,
  please note hardcoding of empty strings in SQL queries breaks execution in Oracle database.
+* Indexes must not be defined on the same columns as keys, this is now reported as fatal problem.
+  Please note that internally we create indexes instead of foreign keys.

 YUI changes:
 * M.util.help_icon has been deprecated. Code should be updated to use moodle-core-popuphelp