From 20219dd4f7192c61492b7667dd3f15b05dbba044 Mon Sep 17 00:00:00 2001
From: Martin Kagamino Lehoux <martin@lehoux.net>
Date: Sat, 23 Sep 2023 20:19:44 +0200
Subject: feat: Add post to version control

---
 .../posts/postgres-aggregates/sequential-ctes.sql  | 28 ++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 content/posts/postgres-aggregates/sequential-ctes.sql

(limited to 'content/posts/postgres-aggregates/sequential-ctes.sql')

diff --git a/content/posts/postgres-aggregates/sequential-ctes.sql b/content/posts/postgres-aggregates/sequential-ctes.sql
new file mode 100644
index 0000000..fa18acd
--- /dev/null
+++ b/content/posts/postgres-aggregates/sequential-ctes.sql
@@ -0,0 +1,28 @@
+-- EXPLAIN (ANALYZE, COSTS, VERBOSE, BUFFERS)
+WITH product_with_reviews AS (
+  SELECT
+    products.id AS product_id,
+    products.name AS product_name,
+    COUNT(reviews.id) AS num_reviews
+  FROM
+    products
+    LEFT JOIN reviews ON reviews.product_id = products.id
+    -- WHERE
+    --   products.id % 10 = 0
+  GROUP BY
+    products.id,
+    products.name
+)
+SELECT
+  product_with_reviews.product_id,
+  product_name,
+  num_reviews,
+  COUNT(id) AS num_orders
+FROM
+  product_with_reviews
+  LEFT JOIN orders ON orders.product_id = product_with_reviews.product_id
+GROUP BY
+  product_with_reviews.product_id,
+  product_name,
+  num_reviews;
+
-- 
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