[Solved] Identify the error in this query to find gaps:SELECT num + 1 AS missing FROM seq WHERE num + 1 = LEAD(num) OVER (ORDER BY num); | SQL

SQL - Advanced Query Patterns

Identify the error in this query to find gaps:

SELECT num + 1 AS missing FROM seq WHERE num + 1 = LEAD(num) OVER (ORDER BY num);

Anum + 1 should be replaced with num - 1

BMissing GROUP BY clause

CUsing '=' instead of '<>' causes no gaps to be found

DLEAD() cannot be used without PARTITION BY

Step-by-Step Solution

Solution:

Step 1: Understand the condition used
The query checks where num + 1 equals the next num, which means no gap.
Step 2: Correct condition for gaps
To find gaps, we want num + 1 not equal to next num, so '<>' is needed.
Final Answer:
Using '=' instead of '<>' causes no gaps to be found -> Option C
Quick Check:
Equality check hides gaps [OK]

Quick Trick: Use '<>' to detect gaps, not '=' [OK]

Common Mistakes:

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