internal/db: add migration for static credential table

The static credential table is used rather than the credential
table as all credentials returned by ListCredentials are static
at this time.

internal/db/schema/migrations/oss/postgres/46/01_credentials.up.sql

@@ -97,6 +97,7 @@ begin;
   -- insert_credential_static_subtype() is a before insert trigger
   -- function for subtypes of credential_static
   -- Replaces the insert_credential_static_subtype function defined in 10/03_credential.up.sql
+  -- Replaced in 79/03_credential_static_base_table_updates.up.sql
   create or replace function insert_credential_static_subtype() returns trigger
   as $$
   begin

internal/db/schema/migrations/oss/postgres/80/03_credential_static_base_table_updates.up.sql

@@ -0,0 +1,69 @@
+-- Copyright (c) HashiCorp, Inc.
+-- SPDX-License-Identifier: BUSL-1.1
+
+begin;
+
+  -- Add create_time and update_time to credential_static table.
+  alter table credential_static add column create_time wt_timestamp;
+  alter table credential_static add column update_time wt_timestamp;
+
+  -- Update rows with current values
+  update credential_static
+    set create_time = csj.create_time, update_time = csj.update_time
+    from credential_static as cs
+    left join credential_static_json_credential as csj on cs.public_id = csj.public_id;
+  update credential_static
+    set create_time = cssshpk.create_time, update_time = cssshpk.update_time
+    from credential_static as cs
+    left join credential_static_ssh_private_key_credential as cssshpk on cs.public_id = cssshpk.public_id;
+  update credential_static
+    set create_time = csupw.create_time, update_time = csupw.update_time
+    from credential_static as cs
+    left join credential_static_username_password_credential as csupw on cs.public_id = csupw.public_id;
+
+  -- Replace the insert trigger to also set the create_time
+  -- Replaces the insert_credential_static_subtype function defined in 46/01_credentials.up.sql
+  create or replace function insert_credential_static_subtype() returns trigger
+  as $$
+  begin
+    select project_id into new.project_id
+      from credential_store
+     where credential_store.public_id = new.store_id;
+
+    insert into credential_static
+      (public_id, store_id, project_id, create_time)
+    values
+      (new.public_id, new.store_id, new.project_id, new.create_time);
+    return new;
+  end;
+  $$ language plpgsql;
+
+  -- Add trigger to update the new update_time column on every subtype update.
+  create function update_credential_static_table_update_time() returns trigger
+  as $$
+  begin
+    update credential_static set update_time = now() where public_id = new.public_id;
+    return new;
+  end;
+  $$ language plpgsql;
+  comment on function update_credential_static_table_update_time() is
+    'update_credential_static_table_update_time is used to automatically update the update_time '
+    'of the base table whenever one of the subtype tables are updated';
+
+  -- Add triggers to subtype tables
+  create trigger update_credential_static_table_update_time before update on credential_static_json_credential
+    for each row execute procedure update_credential_static_table_update_time();
+  create trigger update_credential_static_table_update_time before update on credential_static_ssh_private_key_credential
+    for each row execute procedure update_credential_static_table_update_time();
+  create trigger update_credential_static_table_update_time before update on credential_static_username_password_credential
+    for each row execute procedure update_credential_static_table_update_time();
+
+  -- Add new indexes for the create and update time queries.
+  create index credential_static_create_time_public_id_idx
+      on credential_static (create_time desc, public_id asc);
+  create index credential_static_update_time_public_id_idx
+      on credential_static (update_time desc, public_id asc);
+
+  analyze credential_static;
+
+commit;

internal/db/sqltest/tests/pagination/credential.sql

@@ -0,0 +1,33 @@
+-- Copyright (c) HashiCorp, Inc.
+-- SPDX-License-Identifier: BUSL-1.1
+
+begin;
+  select plan(10);
+
+  -- Verify the trigger functions exist and are declared properly
+  select has_function('update_credential_static_table_update_time');
+  select volatility_is('update_credential_static_table_update_time', 'volatile');
+  select isnt_strict('update_credential_static_table_update_time');
+  select has_trigger('credential_static_json_credential', 'update_credential_static_table_update_time');
+  select has_trigger('credential_static_ssh_private_key_credential', 'update_credential_static_table_update_time');
+  select has_trigger('credential_static_username_password_credential', 'update_credential_static_table_update_time');
+  select has_index('credential_static', 'credential_static_create_time_public_id_idx', array['create_time', 'public_id']);
+  select has_index('credential_static', 'credential_static_update_time_public_id_idx', array['update_time', 'public_id']);
+
+  -- To test that the trigger that sets the create_time of the base table
+  -- when an insert into a subtype table happens works, we check that the
+  -- create time of the entries in both tables match
+  prepare credential_static_create_time as select create_time from credential_static where public_id='csj__bcolors';
+  prepare credential_static_json_credential_create_time as select create_time from credential_static_json_credential where public_id='csj__bcolors';
+  select results_eq('credential_static_create_time','credential_static_json_credential_create_time');
+  -- To test the trigger that updates the update_time of the base table,
+  -- we update one of the existing creds and check that the base table
+  -- entry has the same update_time as the subtype one.
+  update credential_static_json_credential set name='Blue black json cred' where public_id='csj__bcolors';
+  prepare credential_static_update_time as select update_time from credential_static where public_id='csj__bcolors';
+  prepare credential_static_json_credential_update_time as select update_time from credential_static_json_credential where public_id='csj__bcolors';
+  select results_eq('credential_static_update_time','credential_static_json_credential_update_time');
+
+  select * from finish();
+
+rollback;