schema: add delete cascade constraints to foreign keys

sql/swh-vault-schema.sql

@@ -40,7 +40,7 @@ create index concurrently vault_bundle_task_id
 create table vault_notif_email (
   id bigserial primary key,
   email text not null,              -- e-mail to notify
-  bundle_id bigint not null references vault_bundle(id)
+  bundle_id bigint not null references vault_bundle(id) on delete cascade
 );
 create index concurrently vault_notif_email_bundle
   on vault_notif_email (bundle_id);
@@ -52,8 +52,8 @@ create table vault_batch (
 );
 
 create table vault_batch_bundle (
-  batch_id bigint not null references vault_batch(id),
-  bundle_id bigint not null references vault_bundle(id)
+  batch_id bigint not null references vault_batch(id) on delete cascade,
+  bundle_id bigint not null references vault_bundle(id) on delete cascade
 );
 create unique index concurrently vault_batch_bundle_pkey
   on vault_batch_bundle (batch_id, bundle_id);

sql/upgrades/003.sql

+-- SWH DB schema upgrade
+-- from_version: 002
+-- to_version: 003
+-- description: Add delete cascade conditions
+
+insert into dbversion(version, release, description)
+    values(3, now(), 'Add delete cascade conditions');
+
+alter table vault_notif_email
+    drop constraint "vault_notif_email_bundle_id_fkey",
+    add constraint "vault_notif_email_bundle_id_fkey"
+    foreign key(bundle_id)
+    references vault_bundle
+    on delete cascade;
+
+alter table vault_batch_bundle
+    drop constraint "vault_batch_bundle_bundle_id_fkey",
+    add constraint "vault_batch_bundle_bundle_id_fkey"
+    foreign key(bundle_id)
+    references vault_bundle
+    on delete cascade;
+
+alter table vault_batch_bundle
+    drop constraint "vault_batch_bundle_batch_id_fkey",
+    add constraint "vault_batch_bundle_batch_id_fkey"
+    foreign key(batch_id)
+    references vault_batch
+    on delete cascade;