1. Store a value
SET writes a string value to a key, creating or overwriting it.
SET user:1 "Ada"Typorithm · easy
SET, GET & TTL
redis-set-getredissetttlexpire
Saved on this device
Full lesson · 8 learning steps Open any exercise for focused practice
10%
Step 1 of 8 · intro card
Learn SET, GET & TTL
Strings & Keys
SET stores a string value at a key and GET reads it back; the EX option attaches a seconds-based expiry, TTL reports the remaining life, and DEL removes a key entirely.
Redis keys are flat strings and values default to strings, so SET user:1 "Ada" simply stores the text Ada under the key user:1, and GET user:1 reads it straight back.
Adding EX 3600 to a SET gives the key a time-to-live of 3600 seconds; once that window elapses Redis evicts the key automatically. TTL session:42 reports how many seconds remain.
DEL user:1 removes a key and its value on the spot. TTL also doubles as a probe: it returns -1 for a key with no expiry and -2 for a key that no longer exists.
01
SET writes a string value; GET reads it.
02
EX <seconds> on SET sets a time-to-live.
03
TTL reports remaining life; DEL removes a key.
SET user:1 "Ada"
GET user:1
SET session:42 "tok" EX 3600
TTL session:42
DEL user:1Read the implementation
Connect each part of the code to the concept before you type.
2. Read a value
GET returns the string value stored at a key, or nil if it does not exist.
GET user:13. Set with expiry
The EX option gives the key a time-to-live in seconds — here 3600 (one hour).
SET session:42 "tok" EX 36004. Query remaining life
TTL returns the seconds left before a key expires (-1 if it has no expiry, -2 if it is gone).
TTL session:425. Remove a key
DEL deletes a key and its value immediately.
DEL user:1A complete learning loop
01
Understand
Read the concept map and follow the code breakdown.
02
Reconstruct
Type the implementation, repair mistakes and work through every recall exercise.
03
Verify
Use the final check without hints; revisit weak concepts in short practice sessions.