[Solved] Identify the error in this query:SELECT category, SUM(CASE category = 'Books' THEN 1 ELSE 0 END) AS books_count FROM products GROUP BY category; | SQL

SQL - Advanced Query Patterns

Identify the error in this query:

SELECT category, SUM(CASE category = 'Books' THEN 1 ELSE 0 END) AS books_count FROM products GROUP BY category;

AGROUP BY should include books_count

BSUM cannot be used with CASE

CMissing WHEN keyword in CASE statement

Dcategory column missing in SELECT

Step-by-Step Solution

Solution:

Step 1: Check CASE syntax
CASE requires WHEN before condition; here it is missing.
Step 2: Validate other parts
GROUP BY and SELECT columns are correct; SUM with CASE is valid.
Final Answer:
Missing WHEN keyword in CASE statement -> Option C
Quick Check:
CASE syntax requires WHEN before condition [OK]

Quick Trick: CASE must have WHEN before condition [OK]

Common Mistakes:

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