Data Management Capabilities > Using Excel to Export and Import Data > About Importing Data from Excel > Considerations for Importing All Data > Considerations for Importing Product Structures or BOMs
  
Considerations for Importing Product Structures or BOMs
When you import product structures from Microsoft Excel to Windchill PDMLink, consider the following:
When you import changes to a product structure, you do not need to import the entire product structure. Each row in the product structure is considered a discrete action. For example, if you want to add one part to an existing product structure, simply specify the parent assembly and the row with the new part added.
If a component part exists at multiple levels of a structure, import from spreadsheet must reuse the same child parts for that component part at all levels of the structure. If, in the spreadsheet, the component part does not have the same child parts at all levels, the first occurrence defines the child parts at all levels.
Import from Spreadsheet does not load sub-component if the parent component is loaded more than one time
For more information on the spreadsheet format, see File Format for Importing Product Structures or BOMs.
When you import a product structure, a new baseline is created for each worksheet.
You must have Create permission for the ManagedBaseline type.
If you specified the name for the baseline, it is used as a prefix. If you do not specify a name, the baseline is assigned a name using the following syntax:
<prefix>-<year><month><date><hour><minute><seconds>
where <prefix> is the baseline name entered by you; or, if you left the baseline name blank, the file name of the import spreadsheet without the extension.
Imported product structures must reference parts that already exist in Windchill PDMLink. If a part referenced in the product structure does not exist, import fails.
If you need to import a product structure with parts that do not yet exist in Windchill PDMLink, import one spreadsheet that contains both the new parts and the product structure.
If an import spreadsheet contains both new parts and product structure information, you can skip the validation step and import the spreadsheet successfully.
If you import a modified product structure, existing product structure links that are not included in the import spreadsheet do not change.
If you create a new product structure, each row in the worksheet describes the Add action. If you modify an existing product structure, each row in the worksheet describes either the add or delete action.
If you need to modify a quantity within the product structure, use the Add action and specify the new quantity. The Delete action removes the part and all its quantities from the product structure, but does not delete the part from Windchill.
When importing a product structure, you can include reference designators in the input spreadsheet under the Reference Designators column. An error appears if the values in the Reference Designators column do not match the numbers in the Quantity column.
An error appears if you are remove a child part with a particular line number and adding another child part with same line number. To avoid this error, remove all child parts and then bulk load the child parts with the desired line number.