SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07cba230aff02764505b3140fa6600eb09c743d76e3ff551c83de89752ffb3e5' 
  AND token = '832wlpT6UwLSjPLXgWhdmLLyVLOrFB5v2qfvkpZhytQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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