[Solved] Find the error in this query:WITH cte1 AS (SELECT 10), cte2 AS (SELECT val FROM cte1) SELECT * FROM cte2; | PostgreSQL

PostgreSQL - Common Table Expressions

Find the error in this query:

WITH cte1 AS (SELECT 10), cte2 AS (SELECT val FROM cte1) SELECT * FROM cte2;

Acte1 does not define column alias 'val'

BMissing comma between CTE definitions

CIncorrect use of SELECT * in final query

DCTEs cannot reference each other

Step-by-Step Solution

Solution:

Step 1: Check cte1 definition
cte1 selects 10 but does not assign a column name.
Step 2: Check cte2 usage
cte2 tries to select 'val' from cte1, but 'val' column does not exist.
Final Answer:
cte1 does not define column alias 'val' -> Option A
Quick Check:
Always alias columns in CTEs if referenced later [OK]

Quick Trick: Alias columns if referenced later [OK]

Common Mistakes:

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