Junior vs Senior: Databricks "MERGE INTO" Code Review

How seniors review for reliability, not syntax.

I watched a senior review a Databricks MERGE statement. Approved code in 2 min. Spent 20 min on edge cases. That’s the senior difference.

Code review is where the gap between junior and senior thinking is most visible.

It’s not about syntax anymore - AI gets that right 90% of the time.

Here’s what I’m seeing separate juniors from seniors:

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❌ 𝗧𝗵𝗲 𝗝𝘂𝗻𝗶𝗼𝗿 𝗧𝗿𝗮𝗽: 𝗦𝘆𝗻𝘁𝗮𝘅 𝗣𝗼𝗹𝗶𝗰𝗲

The junior reviews the pull request like a spellchecker.

𝗪𝗵𝗮𝘁 𝘁𝗵𝗲𝘆 𝗳𝗼𝗰𝘂𝘀 𝗼𝗻:

- Variable naming conventions (snake_case vs camelCase)

- Indentation and formatting

- Typos in comments

- Whether the code “looks clean”

Why this limits them: They are checking if the code is _written_ correctly, not if it _works_ correctly in the system.

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✅ 𝗧𝗵𝗲 𝗦𝗲𝗻𝗶𝗼𝗿 𝗔𝗽𝗽𝗿𝗼𝗮𝗰𝗵: 𝗥𝗲𝘀𝗶𝗹𝗶𝗲𝗻𝗰𝗲 𝗔𝘂𝗱𝗶𝘁

The senior assumes the syntax is fine. They look for the invisible failures.