4 posts tagged with "architecture"

Overview​

Since the move to a relational backend, the most common question from the community has been simple: how does it perform against the ODS API? We ran a shared test suite against both APIs, on both PostgreSQL and SQL Server, using the same dataset and request mix.

The short version: on PostgreSQL, Ed‑Fi API 8.1 comes out ahead on every workload we tested. On SQL Server, DeepPaging and FilteredRead are close to a tie, and Volume (writes) is behind. The reason is narrow and well understood: the change-version stamp triggers, the database triggers Ed‑Fi API 8.1 uses to keep each record's _etag, last-modified timestamp, and change-tracking version current on every write. We can point to exactly how much they cost and the work already underway to reduce it.

What This Means for Implementers​

• PostgreSQL: Ed‑Fi API 8.1 wins on writes, paging, and filtered reads against ODS API v7.3.2, on the same hardware and dataset.
• Where the win comes from: mostly a database CPU advantage on reads. The write path is faster too, but that doesn't mean it's cheaper to run across the board (more on that below).
• SQL Server: near ties on paging and filtered reads; behind on writes, traced to the change-version stamp triggers, a mechanism we've measured precisely and already scoped a fix for (see below).
• Read this as a snapshot, not a guarantee for your deployment. See the caveats in the "How We Tested" section below.

Overview​

The Ed‑Fi Data Management Service (DMS) is evolving toward a relational backend, shaped by community feedback and real‑world implementation experience. Building on the proven Ed‑Fi ODS/API foundation, DMS modernizes the storage layer to address long‑standing operational challenges—such as wide composite keys and complex joins—through targeted structural changes.

By prioritizing a relational backend, DMS preserves the core strengths of the ODS: predictable schemas, strong referential integrity, and compatibility with relational tooling. The result is a service that feels familiar to teams with ODS experience and lowers the cognitive and migration cost of adoption.

What This Means for Implementers​

If you work directly with the ODS database today, DMS's data store will feel familiar, but with important structural differences:

• You still work with the same Ed‑Fi entities and natural keys
• Joins are simpler and narrower due to surrogate keys
• Person identity is clearer and no longer mediated by ODS-only integers
• Optional document caching can accelerate API reads

The sections below explain why these changes exist and how they affect database design and operations.

This post is written for database administrators, backend developers, data engineers, and solution architects who work with the Ed‑Fi ODS/API at the database level and are evaluating or planning a transition to DMS. Familiarity with the ODS schema and relational database concepts is assumed.

Tech Congress 2025 is just over a month away and Project Tanager Milestone 0.4.0 has been reached. Can you help us show off what it is (or might be) capable of?

Think of this as a call for posters. If you're not familiar with academic conferences and posters... then maybe you can imagine a science fair board. Do something cool, show it off in a few words and some pictures, and you get a few minutes to narrate for your audience. Complete your "poster" before April 17 so that I have time to incorporate it into a slide deck for an April 23 Tech Congress session showing off the Data Management Service in Action.

The recent Ed-Fi blog post New Cloud-Native Functionality Coming to the Ed-Fi Alliance Technology Suite introduced a piece of software under active development, the Ed-Fi Data Management Service.

Eventually, this software will replace the Ed-Fi ODS/API Platform. Unsurprisingly, a few themes emerged in the questions and conversations at Ed-Fi Tech Congress 2024. We've begun addressing those in a new Frequently Asked Questions page in the Project Tanager repository. And we'll continue adding questions and answers on that page as they come upk.