SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '60ef23a31a899d0ef64b570a442798905fd72b789d8b44cfd31bad2c2609fe44' 
  AND token = 'MA3zjPcygUmrJ7cvZ/hHIg8NWf6AC+FxLQb940NBhJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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