[D1] Add changelog entry for free tier daily query limit enforcement

src/content/changelog/d1/2026-09-01-d1-free-tier-limit-enforcement.mdx

@@ -0,0 +1,20 @@
+---
+title: D1 enforces free tier daily query limits
+description: Beginning September 1, 2026, D1 queries on Workers Free accounts that exceed daily row read or row write limits will fail and return errors.
+products:
+  - d1
+date: 2026-09-01
+---
+
+Beginning September 1, 2026, D1 queries on the [Workers Free plan](/workers/platform/pricing/#workers) will fail when an account exceeds the daily [row read or row write limits](/d1/platform/pricing/). Queries via the [Workers Binding API](/d1/worker-api/) and the [REST API](/d1/rest-api/) will return errors until the limit resets at midnight UTC. Stored data is not affected.
+
+You will receive email alerts when the daily limit is reached. The following errors indicate that a limit has been exceeded:
+
+| Error | Description |
+|-------|-------------|
+| Your account has exceeded D1's free tier daily row read limit. Upgrade to a paid plan or wait until tomorrow (midnight UTC) to continue. | The account has reached its daily row read limit. |
+| Your account has exceeded D1's free tier daily row write limit. Upgrade to a paid plan or wait until tomorrow (midnight UTC) to continue. | The account has reached its daily row write limit. |
+
+Inspect database query activity before the enforcement date to identify queries that may exceed these limits. To reduce row reads, add [indexes](/d1/best-practices/use-indexes/) to tables and review queries that perform full table scans. If usage requires higher limits after optimization, upgrade to a [Workers Paid plan](/workers/platform/pricing/#workers).
+
+For more information on D1 errors and how to handle them, refer to the [D1 error list](/d1/observability/debug-d1/#error-list).