SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4fbbbff3c0fa849a789c0ff8ac22291f4911a62fb8f0842ddf5608957b36962' 
  AND token = 'i1KGHWcEvdQ1YA0tLFrcxjajiMMQDpjTfhtSE7g1byU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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