Programming · Flashcard
An UPDATE runs with no WHERE clause. What happens?
- AEvery row is updated, with no warning at all
- BThe statement is rejected, since UPDATE requires a WHERE
- COnly the first row is updated, as a safety default
- DNothing changes until a WHERE clause is supplied
Why this is the answer
A missing WHERE means every row matches, and the server does it without comment — which is why this is the classic production incident and why clients such as psql offer no protection. Wrapping the statement in a transaction and checking the row count before COMMIT is the habit that saves you.
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