Added 'ON DELETE CASCADE' instruction.

Signed-off-by: Cristiano Urban <cristiano.urban@inaf.it>

00-init.sql

@@ -90,7 +90,7 @@ CREATE TABLE node (
     -- storage_id            VARCHAR,    
     protocols              TEXT[]        default NULL,
     PRIMARY KEY (node_id),
-    FOREIGN KEY (location_id) REFERENCES location (location_id)
+    FOREIGN KEY (location_id) REFERENCES location (location_id) ON DELETE CASCADE
 );
 
 
@@ -132,7 +132,7 @@ CREATE TABLE deleted_node (
     -- add a deleted_on timestamp to keep track
     deleted_on             TIMESTAMP     default CURRENT_TIMESTAMP,
     PRIMARY KEY (node_id),
-    FOREIGN KEY (location_id) REFERENCES location (location_id)
+    FOREIGN KEY (location_id) REFERENCES location (location_id) ON DELETE CASCADE
 );