SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '480f5056273a468ae2bbceb1bd942e7456b33b384a13a2e010ae39e764be0fec' 
  AND token = 'P0Bzti6tpxmolbYnlOFzDrxyiqBPMOx0rUmoGFPJNB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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