Create dim_purchaseable model

[rachellougee]

Description/Context

As part of #1325, we need a dimensional table to Include information about elements of content and
services that can be sold for >=$0 (e.g. programs, course runs, bootcamps,
subscriptions, etc.)

Plan/Design

Create a dim_purchaseable/product model including the following fields:

id - hashed primary key
readable_id
name
type (e.g. program, course run)
price
more attributes?

The data sources will include MITx Online, xPro, edxorg, bootcamps, and residential

[rachellougee]

@blarghmatey Kate and I discussed product_price in this table. @KatelynGit thinks the price should go to tfact_purchase since it's numeric and measurable. I think it should go to dim_purchaseable/product table (Slowly Changing Dimension if needed) since it is an attribute of a product, especially since the price is the same across users' transactions. That way we would avoid redundancy and can easily query the products with no purchase history. If price changes I just wanted us to be on the same page. What do you think?

[blarghmatey]

I think that it should go in both places, treating the dim_purchaseable as a type 2 SCD, since price isn't static.

[rachellougee]

I think that it should go in both places, treating the dim_purchaseable as a type 2 SCD, since price isn't static.

That makes sense. We can create dim_purchaseable as Slowly Changing Dimension Type 2 to keep the changes. Currently, the table is loaded as a full refresh in airbyte. Do we need to modify the staging table or implement the new model to capture the changes in dbt instead? The price isn't changed that often as far as I can tell though