Database / ValKey Interview questions

How do you apply a TTL to a key in Valkey?

A time-to-live can be attached when a key is created or added afterward, and Valkey will automatically remove the key once it expires.

SET session:1001 "user-data"
EXPIRE session:1001 3600        # expire in 3600 seconds

SET session:1002 "user-data" EX 3600   # set + TTL in one command

TTL session:1001                # check remaining seconds
PERSIST session:1001            # remove the expiration

PEXPIRE/PTTL offer millisecond precision, and EXPIRE supports NX/XX/GT/LT flags to conditionally set a TTL relative to any existing one.

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Which command removes an expiration from a key while keeping its value? PERSIST

✓ Correct! Well done.

TTL

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EXPIRE

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DEL

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SET key value EX 60 is functionally equivalent to... setting the key and then running EXPIRE key 60

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setting the key with no expiration at all

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deleting the key after 60 reads

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limiting the value to 60 bytes

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Database / ValKey Interview questions

How do you apply a TTL to a key in Valkey?

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