> For the complete documentation index, see [llms.txt](https://help.holixa.com/holixa-tools4inventor/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.holixa.com/holixa-tools4inventor/commands-overview/bom/update.md).
# Update
## Command Description
The Update command updates all structured item numbers in dependent subassemblies of the current (main) assembly.
{% hint style="danger" %}
For new Inventor versions, this command is obsolete because Inventor updates the items automatically.
{% endhint %}
{% hint style="info" %}
This command acts on the current active assembly only.
{% endhint %}
{% hint style="warning" %}
This command is to be run in the main assembly only.
{% endhint %}
A schematic image of the process is in the image below.
Update command workflow
### Summary of changes to the BOM performed by the command (a comparison matrix)
The comparison matrix of BOM manipulation tools
## Command Location
* Assembly environment (`Be.Smart T4I -> BOM panel`, `Assemble -> Manage panel`).
## Command Settings
This command has no settings.
## Workflow Overview
1. Change the structured item number of the subassembly.
2. Run the command.
## Description of changes performed by the command
First, only the subassembly item number was changed. After running the command, all dependant item numbers were updated.
| Structured main assembly BOM after changing the subassembly item number | Subassembly item numbers after applying the command |
| ----------------------------------------------------------------------- | --------------------------------------------------- |
|  |  |