SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1612102581efe412d7fb765ddbb2b24d17d24fb7ac97db6aee3b993d611f9b7' 
  AND token = 'pKGyDOGhCxbPkhB/99wgesH6XKeWZIqCJmz5MhG+bqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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