SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8167519da9790813695c06a48cdf0289313c0585d124841110cc48620a31833' 
  AND token = 'OlIZWM6nY43MGXKilT6OeXTJ+Tq+9vAzQKmWwljEtrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}