SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24e39743105964f7a363ae9f1f41d71182de3a3723b6597e81c20f5099dcd698' 
  AND token = 'JEYN/45GgRdq9j8ggYTij7GmuCGVfTtNhmti6B3Dvco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00091

JSON explain

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