CLI Basics and Core Commands

Strings

SET greeting "hello"
GET greeting
SET counter 0
INCR counter          # 1
INCRBY counter 5      # 6
SETEX key 60 value    # set with 60s TTL

Keys and Expiry

KEYS *                # list keys (avoid in production)
EXISTS greeting       # 1
TTL key               # seconds until expiry
EXPIRE greeting 120
DEL greeting

Generic Utilities

TYPE key              # string/list/set/hash/zset/stream
RENAME old new
SELECT 1              # switch database
FLUSHDB               # clear current database only

Instrumentation

INFO
MONITOR               # log every command (dev only)
CONFIG GET maxmemory

Key Points

• Strings plus INCR/EXPIRE cover counters and caches.
• TTL and KEYS shape retention and admin.
• SELECT switches logical databases.
• MONITOR is a debugger, never run it in prod traffic.