SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4feeda353d7be2f7a7620fc767be95c4c858ef57b0b3f96587cba3fe971e6fa' 
  AND token = 'KWlkzrlGBT1qZ4SWGcR3dHPCQ0cxPuAQZ6wzIf1unKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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