From 4ff16744b99d06a1820f8e99f778f6cfa7818419 Mon Sep 17 00:00:00 2001
From: Svetlin Zarev <svetlin@zarev.net>
Date: Thu, 28 Nov 2024 11:50:15 +0200
Subject: [PATCH] Replace the unused GIN index with a BTREE index when
 searching by price, because the `->` operator is not accelerated by the GIN
 index

---
 lessons/227/README.md            | 2 +-
 lessons/227/client/store.go      | 2 +-
 lessons/227/migration/0-sql.yaml | 8 ++++----
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/lessons/227/README.md b/lessons/227/README.md
index cbbf9c643..f418b422f 100644
--- a/lessons/227/README.md
+++ b/lessons/227/README.md
@@ -10,7 +10,7 @@ CREATE TABLE product (
     jdoc jsonb
 );
 
-CREATE INDEX product_inx ON product USING GIN (jdoc);
+CREATE INDEX idx__product__price ON product using BTREE(((jdoc -> 'price')::NUMERIC));
 
 INSERT INTO product(jdoc) VALUES ('{"name": "Shampoo", "price": 7.90, "stock": 100}');
 INSERT INTO product(jdoc) VALUES ('{"name": "Hairspray", "price": 11.50, "stock": 100}');
diff --git a/lessons/227/client/store.go b/lessons/227/client/store.go
index 0dbdf0f25..d0d5a9cd0 100644
--- a/lessons/227/client/store.go
+++ b/lessons/227/client/store.go
@@ -34,7 +34,7 @@ func (p *product) create(pg *postgres, mg *mongodb, db string, m *metrics) (err
 
 	if db == "pg" {
 		b, err := json.Marshal(p)
-		fail(err, "json.Marshal(p) filaed")
+		fail(err, "json.Marshal(p) failed")
 
 		err = pg.dbpool.QueryRow(pg.context, `INSERT INTO product(jdoc) VALUES ($1) RETURNING id`, b).Scan(&p.PostgresId)
 
diff --git a/lessons/227/migration/0-sql.yaml b/lessons/227/migration/0-sql.yaml
index adb721220..692dbf29b 100644
--- a/lessons/227/migration/0-sql.yaml
+++ b/lessons/227/migration/0-sql.yaml
@@ -24,13 +24,13 @@ data:
 
     COMMIT;
 
-    VACUUM full;
-
     -- Create Tables
 
     CREATE TABLE product (
       id SERIAL PRIMARY KEY,
       jdoc jsonb
     );
-
-    CREATE INDEX product_inx ON product USING GIN (jdoc);
+    
+    CREATE INDEX idx__product__price ON product using BTREE(((jdoc -> 'price')::NUMERIC));
+    
+    VACUUM full;