SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e25a97cae0ce8244afbbb2ad5555c244cb92e66b697436c1c2e9bca8b757bfd8' 
  AND token = 'YTHL8n8Ppq4vdvGz7bRjuMFScwcYQb1lRbs/OZ1AMgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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