Do not null destination row values when source deleted

paulmwatson — Fri, 20 Feb 2026 13:29:38 GMT

How do we configure Stitch CDC Log-Based Incremental Replication (from MongoDB Atlas to AWS RDS PostgreSQL) to not null values in destination rows when a source document is deleted?

We end up with rows like this:

_id	_sdc_batched_at	_sdc_extracted_at	_sdc_received_at	_sdc_sequence	_sdc_table_version	name	_sdc_deleted_at
687a35b9606062c59c5a5428	2026-02-19 19:12:16.465+00	2026-02-19 19:04:11.522+00	2026-02-19 19:04:31+00	1771527862209286200	1771513244411	ACME Inc	NULL
687a35f9606062c59c5a67ae	2026-02-19 19:12:16.466+00	2026-02-19 19:04:11.522+00	2026-02-19 19:04:31+00	1771527862209315701	1771513244411	Nala Bing	NULL
698e6c34fa53f8ab7e921e4c	2026-02-20 07:02:25.878+00	2026-02-20 07:01:47.149+00	2026-02-20 07:02:09+00	1771570907959430902	1771513244411	NULL	2026-02-20 06:47:20+00
698dc416c7e4363d38349382	2026-02-20 07:02:25.878+00	2026-02-20 07:01:47.149+00	2026-02-20 07:02:09+00	1771570907959422701	1771513244411	NULL	2026-02-20 06:47:18+00

So e.g. the first row: document `687a35b9606062c59c5a5428` was deleted in MongoDB and Stitch then sets `_sdc_deleted_at` correctly but it nulls `name`. The `name` value was there before the source document was deleted and that change was replicated.

Re: Do not null destination row values when source deleted

Soheb_Algur — Tue, 24 Mar 2026 14:11:37 GMT

Hello @paulmwatson,

What you're seeing is actually expected behavior with log based CDC replication in Stitch.

When a document is deleted in MongoDB the change stream only includes the document's _id and some metadata about the operation it doesn't include the full document fields (like name). Because of that, Stitch has no way to retain the previous values when processing a delete.

As per the documentation, Stitch handles this by overwriting the existing row:

The primary key (_id) is preserved

_sdc_deleted_at is populated with the deletion timestamp

All other columns are set to NULL

So what you end up with is essentially a tombstone record it marks that the document was deleted, but it doesn't keep the original field values.

At the moment, there isn't a configuration option in Stitch to change this behavior for log based replication.

If retaining the field values after deletion is important for your use case, you could consider a couple of alternatives:

Use soft deletes in MongoDB
Instead of deleting documents, add a field like deleted_at. This way, Stitch treats it as an update and keeps all the column values intact.

Use a different replication method
Full-table replication can preserve values, but it comes with trade offs like higher load.

This behavior is also described in the Stitch docs under Hard deletes with Log based Incremental:
https://www.stitchdata.com/docs/replication/deleted-record-handling

Hope this helps clarify things!

topic Re: Do not null destination row values when source deleted in Stitch

Do not null destination row values when source deleted

Re: Do not null destination row values when source deleted