[Solved] Identify the error in this recursive CTE:WITH RECURSIVE cte AS (SELECT 1 AS n UNION SELECT n + 1 FROM cte WHERE n < 5) SELECT * FROM cte; | SQL

SQL - Common Table Expressions (CTEs)

Identify the error in this recursive CTE:

WITH RECURSIVE cte AS (SELECT 1 AS n UNION SELECT n + 1 FROM cte WHERE n < 5) SELECT * FROM cte;

AIncorrect base SELECT syntax

BCTE name is invalid

CMissing UNION ALL keyword causes infinite recursion

DWHERE clause should be outside the CTE

Step-by-Step Solution

Solution:

Step 1: Check recursive CTE syntax
Recursive CTEs require UNION ALL to combine base and recursive parts to avoid infinite loops.
Step 2: Identify missing UNION ALL
This query uses UNION instead of UNION ALL, causing the recursion to not terminate properly.
Final Answer:
Missing UNION ALL keyword causes infinite recursion -> Option C
Quick Check:
Use UNION ALL in recursive CTEs [OK]

Quick Trick: Recursive CTEs must use UNION ALL, not UNION [OK]

Common Mistakes:

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