Build Script: setting the id?

In a couple of the tutorial docs (e.g. http://rtfm.modx.com/display/revolution20/Developing+an+Extra+in+MODX+Revolution%2C+Part+III), the build script sets an ID verbosely when creating a category, e.g.:



Is that right? That's soooo confusing: you would never force the primary key like that normally. Can someone explain this?

Definitely should not need to set it, though it will not use this primary key when being installed if unique_key is specified and/or preserve_keys is false.

Thank you Jason -- gonna update the docs....

In some cases, it may be used to key related objects stored along with it, and though it will not be preserved when inserted (unless preserve_keys == true), it is important in the representation of the relationship.

So is it like the hard-coded id is a placeholder of some kind? So if your build script might hard-code ids 1-10 to preserve relationships with related objects, but when they actually get inserted, they may end up with ids 53 to 62 or something?

Correct. When you package related objects together in a single vehicle and set the attribute for preserve_keys to false (or define a unique_key that does not include the primary key), they preserve their foreign key relationships and resolve those FK column values when being installed.