SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6541fe36f8227df4abe19d07e16ce75147bd0af4ecc361813eb5f619ac4b04e' 
  AND token = 'vWxP6NHKDpuFw+mPo+qbO6xbwI4B08yg2/W+GjqhRlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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