SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06f7fc3405b862bf65c416ba2084889b26ff8bfc9f89ad9abd8f496c3882bfba' 
  AND token = 'O7Mp3xoPL5G5a9i4ASb75lYwzWiQjTz0zWPgbniBb2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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