SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '952280ba3b62c6e31d9951be088e0e13effc4141af2315363b19d1f1a579ce8a' 
  AND token = 'yG70NV620/BObjmc2sx1fsTOBs5GMwQgJY1EZonZm24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}