SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da5a90824d9ebd8197ae4f57975846dcbaf0f1ca1e7a6991a6445458d3d2cc6a' 
  AND token = 'yBcuq2XoBMg3KkMhWX/eeRTeQbCSNC8Ya08P7QnFzbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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