GUACAMOLE-52: Foreign keys in history table should be ON DELETE SET NULL. For sake of context, always store username and connection name in history table.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-mysql/schema/upgrade/upgrade-pre-0.9.10.sql

@@ -0,0 +1,89 @@
+--
+-- Licensed to the Apache Software Foundation (ASF) under one
+-- or more contributor license agreements.  See the NOTICE file
+-- distributed with this work for additional information
+-- regarding copyright ownership.  The ASF licenses this file
+-- to you under the Apache License, Version 2.0 (the
+-- "License"); you may not use this file except in compliance
+-- with the License.  You may obtain a copy of the License at
+--
+--   http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing,
+-- software distributed under the License is distributed on an
+-- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+-- KIND, either express or implied.  See the License for the
+-- specific language governing permissions and limitations
+-- under the License.
+--
+
+--
+-- User and connection IDs within history table can now be null
+--
+
+ALTER TABLE guacamole_connection_history
+    MODIFY COLUMN user_id INT(11) DEFAULT NULL;
+
+ALTER TABLE guacamole_connection_history
+    MODIFY COLUMN connection_id INT(11) DEFAULT NULL;
+
+--
+-- Add new username and connection_name columns to history table
+--
+
+ALTER TABLE guacamole_connection_history
+    ADD COLUMN username VARCHAR(128);
+
+ALTER TABLE guacamole_connection_history
+    ADD COLUMN connection_name VARCHAR(128);
+
+--
+-- Populate new name columns by joining corresponding tables
+--
+
+UPDATE guacamole_connection_history
+JOIN guacamole_user
+    ON guacamole_user.user_id = guacamole_connection_history.user_id
+SET guacamole_connection_history.username = guacamole_user.username;
+
+UPDATE guacamole_connection_history
+JOIN guacamole_connection
+    ON guacamole_connection.connection_id =
+        guacamole_connection_history.connection_id
+SET guacamole_connection_history.connection_name =
+    guacamole_connection.connection_name;
+
+--
+-- Set NOT NULL now that the column is fully populated
+--
+
+ALTER TABLE guacamole_connection_history
+    MODIFY username VARCHAR(128) NOT NULL;
+
+ALTER TABLE guacamole_connection_history
+    MODIFY connection_name VARCHAR(128) NOT NULL;
+
+--
+-- Remove old foreign key constraints with ON DELETE CASCADE
+--
+
+ALTER TABLE guacamole_connection_history
+    DROP FOREIGN KEY guacamole_connection_history_ibfk_1;
+
+ALTER TABLE guacamole_connection_history
+    DROP FOREIGN KEY guacamole_connection_history_ibfk_2;
+
+--
+-- Recreate foreign key constraints with ON DELETE SET NULL
+--
+
+ALTER TABLE guacamole_connection_history
+    ADD CONSTRAINT guacamole_connection_history_ibfk_1
+    FOREIGN KEY (user_id)
+    REFERENCES guacamole_user (user_id) ON DELETE SET NULL;
+
+ALTER TABLE guacamole_connection_history
+    ADD CONSTRAINT guacamole_connection_history_ibfk_2
+    FOREIGN KEY (connection_id)
+    REFERENCES guacamole_connection (connection_id) ON DELETE SET NULL;
+