SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfa0d7088f70f3205bcf7a9d26023d40a5d99467f1ce39b0a087e921cc561fcd' 
  AND token = '7QG+1IrwIjLBHE6Mwm6BShItF4u2PVHuRHLfztBJU9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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