feat: Add post to version control

1 files changed, 28 insertions, 0 deletions

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;
+