[Solved] Find the issue in this query:SELECT * FROM orders o LEFT JOIN customers c ON o.customer_id = c.id WHERE c.id = 10; | SQL

SQL - Advanced Joins

Find the issue in this query:

SELECT * FROM orders o LEFT JOIN customers c ON o.customer_id = c.id WHERE c.id = 10;

AWHERE clause filters out unmatched rows, negating LEFT JOIN

BLEFT JOIN should be INNER JOIN for this filter

CMissing GROUP BY clause

DIncorrect table alias usage

Step-by-Step Solution

Solution:

Step 1: Understand LEFT JOIN with WHERE filter
WHERE c.id = 10 excludes rows where c.id is NULL, removing unmatched rows.
Step 2: Effect on LEFT JOIN
This negates the purpose of LEFT JOIN, which is to keep unmatched rows.
Final Answer:
WHERE clause filters out unmatched rows, negating LEFT JOIN -> Option A
Quick Check:
WHERE on joined table column removes unmatched rows [OK]

Quick Trick: WHERE on right table column after LEFT JOIN removes unmatched rows [OK]

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