SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd3b18276b84053a10cbe056a52cf221be5680c9ab4b52643f642a8d1b2910ce5' 
  AND token = 'HVEB2MQEE/BmzpV8exM6tC6JhQKyGGYjweiH6oBwNVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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