SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01f30638ba56af5704527cd327a4bf329625a98e352524667c1a036837c6aea5' 
  AND token = '5+pzRrku84yGWPxZ4jQWPo/zzrN5UHqExqesX9ewazs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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