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Arif Basri
Arif Basri

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How did I learn about Transaction Log, Redo Log, and Undo Log as a developer?

๐Ÿ‘‰ The hard way.

It wasnโ€™t from a course or documentation โ€” it was from bringing down production.

Not because of a DELETE without WHERE, but from a massive delete that quietly filled up the transaction logs and exhausted every bit of allocated space.
Production froze. Everyone looked at the DB.
And the culprit? Me. ๐Ÿ˜…

Iโ€™ve done it twice โ€” once on Sybase (T-log) and once on Oracle (Redo Log).
Different companies, same mistake.

So hereโ€™s my message to all the data analysts and data wranglers:
If youโ€™re using the production database to temporarily store and later delete large analysis datasets โ€” be aware that those deletes are fully logged.

Every delete = undo + redo + log space consumed.
If the log fills up, the whole system can grind to a halt.

โœ… Use NOLOGGING / minimal logging where possible
โœ… Do batched deletes with commits
โœ… Or better yet โ€” donโ€™t use prod as your scratchpad

Your DBA (and your uptime) will thank you. ๐Ÿ™

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