PostgreSQL query with multiple CTEs resulting in unexpected row duplication
I'm prototyping a solution and Can someone help me understand This might be a silly question, but I'm sure I'm missing something obvious here, but I'm sure I'm missing something obvious here, but I'm sure I'm missing something obvious here, but I've been banging my head against this for hours. I'm working with PostgreSQL 13.3 and trying to optimize a query that uses multiple Common Table Expressions (CTEs). The goal is to fetch user details along with their associated orders, but I'm working with unexpected row duplications in the result set. My current query looks like this: ```sql WITH UserDetails AS ( SELECT id, name FROM users WHERE active = true ), Orders AS ( SELECT user_id, COUNT(*) AS order_count FROM orders GROUP BY user_id ) SELECT ud.id, ud.name, o.order_count FROM UserDetails ud LEFT JOIN Orders o ON ud.id = o.user_id; ``` While I expect a unique row for each user in the `UserDetails` CTE, I'm getting duplicated entries for users with multiple orders. I tried using `DISTINCT` on the final SELECT but it didn't resolve the scenario because I still need the order count. I also played with the join conditions but couldn’t find a solution. Is there a correct way to structure this query to avoid duplication while still getting the order count? Any insights would be greatly appreciated! Has anyone else encountered this? I'm working with Sql in a Docker container on Ubuntu 20.04. My development environment is Ubuntu 22.04. Any feedback is welcome! This is part of a larger microservice I'm building. This issue appeared after updating to Sql latest. Any feedback is welcome!