SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22d279ec837b2d91cf645643084c53d7a1eeb1ca5a4494a731b088b46cfa11f5' 
  AND token = 'GAu+Vy3DdDfdkv9GptTveg+rw8vg8ZBYM/XQDnuhTuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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