feat(user-account-merge): add account merge tracking and edX/MIT Learn user mapping

[rachellougee]

What are the relevant tickets?

https://github.com/mitodl/hq/issues/12430

Description (What does it do?)

• New staging models for the MITx Online courserunenrollment/programenrollment audit tables.
• bridge_user_account_link: tracks MITx Online account merges and cross-platform account links (edX.org), derived from enrollment/program audit history.
• edxorg_mitlearn_user_mapping: a standalone reporting table giving a stable edX.org ↔ MIT Learn crosswalk (both connect to MITx Online internally).

A stable way to look up a learner's edX.org and MIT Learn accounts, since usernames/emails on both platforms can change over time.

How can this be tested?

  dbt build --select \                                                                                                                                           
    stg__mitxonline__app__postgres__courses_courserunenrollmentaudit \                                                                                           
    stg__mitxonline__app__postgres__courses_programenrollmentaudit \                                                                                             
    bridge_user_account_link \                                                                                                                                  
    edxorg_mitlearn_user_mapping \

Additional Context

[Copilot]

Pull request overview

Adds dbt models to support cross-platform identity tracking by deriving MITx Online account-merge redirects from enrollment audit history and exposing a stable edX.org ↔ MIT Learn crosswalk via MITx Online.

Changes:

• Introduces new staging models (and source definitions) for MITx Online course run/program enrollment audit logs.
• Adds bridge_user_account_merge dimensional bridge table to track verified MITx Online account-merge redirects.
• Adds edxorg_mitlearn_user_mapping reporting model (with schema docs) for stable cross-platform user mapping.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/ol_dbt/models/staging/mitxonline/stg__mitxonline__app__postgres__courses_programenrollmentaudit.sql	New staging model for program enrollment audit history.
src/ol_dbt/models/staging/mitxonline/stg__mitxonline__app__postgres__courses_courserunenrollmentaudit.sql	New staging model for course run enrollment audit history.
src/ol_dbt/models/staging/mitxonline/_stg_mitxonline__models.yml	Adds schema docs/tests for the new staging audit models.
src/ol_dbt/models/staging/mitxonline/_mitxonline__sources.yml	Registers the new raw audit tables as dbt sources.
src/ol_dbt/models/reporting/edxorg_mitlearn_user_mapping.sql	New reporting crosswalk between edX.org and MIT Learn via MITx Online (+ merge redirects).
src/ol_dbt/models/reporting/_reporting__models.yml	Adds schema docs for the new reporting model.
src/ol_dbt/models/dimensional/bridge_user_account_merge.sql	New bridge table deriving merge redirects from audit history.
src/ol_dbt/models/dimensional/_bridge_tables.yml	Adds schema docs/tests for bridge_user_account_merge.

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[github-actions]

🔎 ol-dbt impact — column-level blast radius

0 breaking, 0 warning, 5 info across 5 changed model(s).

Details

• ℹ️ bridge_user_account_link — from_platform, from_user_id, observed_on, to_platform, to_user_id → 0 downstream model(s)
• ℹ️ bridge_user_account_merge — merged_on, platform, platform_user_id_after, platform_user_id_before → 0 downstream model(s)
• ℹ️ edxorg_mitlearn_user_mapping — edxorg_user_id, mitlearn_application_user_id, mitxonline_openedx_user_id → 0 downstream model(s)
• ℹ️ stg__mitxonline__app__postgres__courses_courserunenrollmentaudit — acting_user_id, courserunenrollment_id, enrollmentaudit_created_on, enrollmentaudit_data_after, enrollmentaudit_data_before, enrollmentaudit_id, enrollmentaudit_updated_on → 0 downstream model(s)
• ℹ️ stg__mitxonline__app__postgres__courses_programenrollmentaudit — acting_user_id, enrollmentaudit_created_on, enrollmentaudit_data_after, enrollmentaudit_data_before, enrollmentaudit_id, enrollmentaudit_updated_on, programenrollment_id → 0 downstream model(s)

_{Posted by ol-dbt impact (annotate-only — does not block merge).}

[KatelynGit]

The builds ran clean, the SQL looked ok to me, but the definitions are odd- they don't look like full sentences, are a bit confusing, and often contain strange characters I'd probably just give them a read through before merging.

[pdpinch]

I just want to emphasize @KatelynGit's comments. The descriptions are meant to be read by our end data platform end users. I know these tables are bit esoteric, but we could at least start with a high-level general statement about what the table is for, before getting into the details about how they are constructed. Perhaps Claude can help.