- Feature
- AL developers can turn indexes on/off in AL code
- Availability
- Generally available (October 2026)
- Industry focus
- Automotive aftermarket and parts distribution
Automotive parts distributors process an enormous number of small transactions. Hundreds of thousands of SKUs, frequent price updates, same-day orders from workshops and constant stock movements all hit the database. In that environment, database indexes are a balancing act. Business Central 29.0 gives app developers a new tool for getting that balance right.
The industry challenge
Indexes make reading data fast. They also make writing data slower and use extra storage, because every index has to be updated when a record changes. For a parts distributor, that trade-off is very real:
- Item ledger entries and value entries grow quickly
- Sales lines, warehouse activity and price records change all day
- Storage in Business Central online has a cost once you exceed your entitlement
Many distributors also run vertical apps or custom extensions that add their own indexes, for example to support cross-reference lookups, supersession chains or vehicle fitment searches. Some of those indexes matter only if a particular feature is switched on. If the customer doesn't use that feature, the index still costs write performance and storage.
Business Central 28.0 already gave administrators a page to view index usage and switch off rarely used, non-unique indexes for each company. But administrators had to make those calls one at a time, without knowing which app features depended on which index.
What Microsoft delivered in Business Central 29.0
In Business Central 29.0, AL developers can turn indexes off and on from AL code. Microsoft's stated purpose is to let app publishers ship index management that matches their features.
An MVP walk-through notes that the methods behind the existing Index Management page are now available to AL, so an app can do in code what an administrator previously did by hand.
In practice, this means an app can:
- Leave an index off until a customer actually enables the feature that needs it
- Turn an index off again when the feature is switched off
- Package index decisions with the feature, instead of leaving them to guesswork after go-live
Where the value shows up
| Business area | Impact for a parts distributor |
|---|---|
| Posting performance | Fewer unnecessary indexes to update on busy tables |
| Storage cost | Less database space spent on indexes for unused features |
| App quality | Vertical apps behave efficiently out of the box |
| Administration | Fewer manual index decisions for the internal IT team |
| Scalability | Better headroom for peak periods |
The benefit isn't a single dramatic speed-up. It's about not paying, in performance and in storage, for capabilities you don't use. At distribution volumes, that adds up.
A worked scenario
Consider a parts distributor that supplies independent garages from four regional depots (an illustrative example). It uses a vertical app that offers vehicle fitment lookups, supersession tracking and a catalogue import tool. The distributor uses supersession heavily but has never switched on the fitment module.
Before, the fitment module's indexes were still maintained on large tables, slowing every catalogue update. Nobody on the internal team knew they could be safely turned off.
With Business Central 29.0, the app publisher updates the app so that fitment indexes are only switched on when the fitment module is enabled. After the update, the distributor's nightly catalogue import runs with less index overhead. If the distributor later enables fitment, the app turns on the indexes it needs.
Adoption considerations
- Ask your app publishers. Find out whether your vertical apps plan to use this capability, and how.
- Measure before and after. Use the index usage information in Business Central to confirm the impact.
- Be careful with custom code. In-house developers should only switch off indexes they fully understand. Turning off the wrong one can slow reports and lookups.
- Document the logic. Record which feature controls which index, so support teams can explain behaviour later.
- Test with real volumes. Index effects show up at scale, so test in a sandbox with production-like data.
The bottom line
Parts distributors win on availability and speed. Their systems need to post thousands of transactions quickly without the database growing out of control. AL-controlled index management in Business Central 29.0 lets the apps that distributors rely on manage their own performance footprint. It's a technical change with a commercial outcome: faster posting and lower storage costs.
If your Business Central database is growing quickly or posting feels slow at peak times, it's worth reviewing index usage with an experienced adviser and your app publishers.
Sources: Microsoft roadmap 573314 · Dynamics 365 Lab: Turn indexes on/off in AL code