From d9d800cfc4f8d49af632418494ae50f2bcff7880 Mon Sep 17 00:00:00 2001
From: Hongbo Wu <hongbo@omnivore.app>
Date: Wed, 10 Jan 2024 17:09:15 +0800
Subject: [PATCH] add index for sorting by saved_at

---
 packages/api/src/services/library_item.ts                | 8 ++++++--
 .../0153.do.library_item_user_id_saved_at_idx.sql        | 6 ++++++
 .../0153.undo.library_item_user_id_saved_at_idx.sql      | 9 +++++++++
 3 files changed, 21 insertions(+), 2 deletions(-)
 create mode 100755 packages/db/migrations/0153.do.library_item_user_id_saved_at_idx.sql
 create mode 100755 packages/db/migrations/0153.undo.library_item_user_id_saved_at_idx.sql

diff --git a/packages/api/src/services/library_item.ts b/packages/api/src/services/library_item.ts
index 8478f33f3..339c7a26d 100644
--- a/packages/api/src/services/library_item.ts
+++ b/packages/api/src/services/library_item.ts
@@ -93,6 +93,7 @@ export enum SortOrder {
 export interface Sort {
   by: string
   order?: SortOrder
+  nulls?: 'NULLS FIRST' | 'NULLS LAST'
 }
 
 interface Select {
@@ -332,8 +333,10 @@ export const buildQuery = (
 
           const order =
             sortOrder === 'asc' ? SortOrder.ASCENDING : SortOrder.DESCENDING
+          const nulls =
+            order === SortOrder.ASCENDING ? 'NULLS FIRST' : 'NULLS LAST'
 
-          orders.push({ by: `library_item.${column}`, order })
+          orders.push({ by: `library_item.${column}`, order, nulls })
           return null
         }
         case 'has':
@@ -613,12 +616,13 @@ export const searchLibraryItems = async (
         orders.push({
           by: 'library_item.saved_at',
           order: SortOrder.DESCENDING,
+          nulls: 'NULLS LAST',
         })
       }
 
       // add order by
       orders.forEach((order) => {
-        queryBuilder.addOrderBy(order.by, order.order, 'NULLS LAST')
+        queryBuilder.addOrderBy(order.by, order.order, order.nulls)
       })
 
       const libraryItems = await queryBuilder.skip(from).take(size).getMany()
diff --git a/packages/db/migrations/0153.do.library_item_user_id_saved_at_idx.sql b/packages/db/migrations/0153.do.library_item_user_id_saved_at_idx.sql
new file mode 100755
index 000000000..9161f6bcf
--- /dev/null
+++ b/packages/db/migrations/0153.do.library_item_user_id_saved_at_idx.sql
@@ -0,0 +1,6 @@
+-- Type: DO
+-- Name: library_item_user_id_saved_at_idx
+-- Description: Add library_item_user_id_saved_at_idx index on library_item table for user_id and saved_at
+
+-- create index for sorting concurrently to avoid locking
+CREATE INDEX CONCURRENTLY IF NOT EXISTS library_item_user_id_saved_at_idx ON omnivore.library_item (user_id, saved_at DESC NULLS LAST);
diff --git a/packages/db/migrations/0153.undo.library_item_user_id_saved_at_idx.sql b/packages/db/migrations/0153.undo.library_item_user_id_saved_at_idx.sql
new file mode 100755
index 000000000..7fc17a292
--- /dev/null
+++ b/packages/db/migrations/0153.undo.library_item_user_id_saved_at_idx.sql
@@ -0,0 +1,9 @@
+-- Type: UNDO
+-- Name: library_item_user_id_saved_at_idx
+-- Description: Add library_item_user_id_saved_at_idx index on library_item table for user_id and saved_at
+
+BEGIN;
+
+DROP INDEX IF EXISTS omnivore.library_item_user_id_saved_at_idx;
+
+COMMIT;