feat(gallery): sort/group/jump by COALESCE(post.post_date, image_record.created_at) — surface migrated content at its original publish date, not FC scan date

Operator hit this 2026-05-25 after the IR tag_apply landed: ~57k images
all scanned into FC in the same week share image_record.created_at, so
the gallery timeline collapses them into a single month bucket and
scroll orders them all together at the top. Their actual publish dates
(spread over years) were already available in Post.post_date but the
gallery never read it.

Backend wire-up:
- tag_apply phase 4 now sets ImageRecord.primary_post_id when creating
  ImageProvenance (only if currently NULL — preserves the canonical
  download-time linkage set by the importer for new FC ingests).
- gallery_service.py introduces _effective_date_col() =
  COALESCE(post.post_date, image_record.created_at), used in:
    * scroll() ORDER BY + cursor WHERE clauses
    * timeline() year/month group-by
    * jump_cursor() year/month filter
    * _neighbors() prev/next ordering
- Each method LEFT OUTER JOIN Post on primary_post_id so the COALESCE
  works for images without a post (NULL on the Post side, fall back
  to created_at).
- GalleryImage gains posted_at + effective_date fields; API /gallery
  /scroll exposes both alongside the existing created_at so the UI
  can render 'Posted on X (imported Y)' if desired.
- get_image_with_tags() returns posted_at for the modal.

Cursor format unchanged — the encoded datetime is now the effective_
date (whichever column won the COALESCE) and pagination remains
consistent.

To pick up new behavior for an already-migrated IR set: re-run
/api/migrate/tag_apply on the existing manifest (phase 4 is
idempotent; the new primary_post_id assignment backfills).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/app/api/gallery.py

@@ -42,6 +42,8 @@ async def scroll():
                     "width": i.width,
                     "height": i.height,
                     "created_at": i.created_at.isoformat(),
+                    "posted_at": i.posted_at.isoformat() if i.posted_at else None,
+                    "effective_date": i.effective_date.isoformat(),
                     "thumbnail_url": i.thumbnail_url,
                     "artist": i.artist,
                 }

backend/app/services/gallery_service.py

@@ -1,26 +1,34 @@
 """Cursor-paginated gallery queries.
 
-Cursor format: opaque base64-encoded "<iso8601_created_at>:<image_id>".
-Pagination key is (created_at DESC, id DESC) so we don't drift when new
-imports arrive between page loads. Decoding rejects malformed cursors with
-a ValueError; the API layer translates that to HTTP 400.
+Cursor format: opaque base64-encoded "<iso8601_effective_date>:<image_id>".
+
+Pagination key is (effective_date DESC, id DESC) where effective_date is
+COALESCE(post.post_date, image_record.created_at) so the gallery surfaces
+images by ORIGINAL publish date when known, falling back to FC's scan
+date. Important for migrated content: ~57k IR images scanned in a single
+week would otherwise all share the same created_at and pile up in one
+month bucket. The effective_date spreads them across the years they
+were originally published.
+
+Decoding rejects malformed cursors with a ValueError; the API layer
+translates that to HTTP 400.
 """
 
 import base64
 from dataclasses import dataclass
 from datetime import datetime
 
-from sqlalchemy import and_, exists, func, or_, select
+from sqlalchemy import Select, and_, exists, func, or_, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from ..models import Artist, ImageProvenance, ImageRecord, Source, Tag
+from ..models import Artist, ImageProvenance, ImageRecord, Post, Source, Tag
 from ..models.tag import image_tag
 
 CURSOR_SEPARATOR = "|"
 
 
-def encode_cursor(created_at: datetime, image_id: int) -> str:
-    raw = f"{created_at.isoformat()}{CURSOR_SEPARATOR}{image_id}"
+def encode_cursor(effective_date: datetime, image_id: int) -> str:
+    raw = f"{effective_date.isoformat()}{CURSOR_SEPARATOR}{image_id}"
     return base64.urlsafe_b64encode(raw.encode()).decode()
 
 
@@ -33,6 +41,26 @@ def decode_cursor(cursor: str) -> tuple[datetime, int]:
         raise ValueError(f"invalid cursor: {cursor!r}") from exc
 
 
+def _effective_date_col():
+    """SQL expression: COALESCE(post.post_date, image_record.created_at).
+
+    Used as the canonical sort/group/filter key across the gallery so
+    images backfilled with primary_post_id (e.g. via tag_apply phase 4)
+    surface at their original publish date, not their FC import date.
+    Images without a Post (or with Post.post_date NULL) fall back to
+    image_record.created_at and still order coherently against
+    post-attached ones.
+    """
+    return func.coalesce(Post.post_date, ImageRecord.created_at)
+
+
+def _outer_join_primary_post(stmt: Select) -> Select:
+    """LEFT JOIN Post on ImageRecord.primary_post_id so the COALESCE
+    above sees Post.post_date when available. Images without a post
+    survive the join as NULL on the Post side; COALESCE handles it."""
+    return stmt.outerjoin(Post, Post.id == ImageRecord.primary_post_id)
+
+
 @dataclass(frozen=True)
 class GalleryImage:
     id: int
@@ -41,7 +69,9 @@ class GalleryImage:
     mime: str
     width: int | None
     height: int | None
-    created_at: datetime
+    created_at: datetime          # FC's row-insert time
+    effective_date: datetime      # COALESCE(post.post_date, created_at)
+    posted_at: datetime | None    # post.post_date if known, else None
     thumbnail_url: str
     artist: dict | None = None
 
@@ -78,7 +108,7 @@ def _require_single_filter(tag_id, post_id, artist_id) -> None:
 def _provenance_clause(post_id, artist_id):
     """Correlated EXISTS clause (NOT a join) so an image with multiple
     matching provenance rows is returned exactly once and the
-    (created_at DESC, id DESC) cursor ordering is unaffected."""
+    (effective_date DESC, id DESC) cursor ordering is unaffected."""
     if post_id is not None:
         return exists().where(
             ImageProvenance.image_record_id == ImageRecord.id,
@@ -125,7 +155,9 @@ class GalleryService:
             raise ValueError("limit must be between 1 and 200")
         _require_single_filter(tag_id, post_id, artist_id)
 
-        stmt = select(ImageRecord)
+        eff = _effective_date_col()
+        stmt = select(ImageRecord, Post.post_date, eff.label("eff"))
+        stmt = _outer_join_primary_post(stmt)
         if tag_id is not None:
             stmt = stmt.join(image_tag, image_tag.c.image_record_id == ImageRecord.id).where(
                 image_tag.c.tag_id == tag_id
@@ -138,34 +170,38 @@ class GalleryService:
             cur_ts, cur_id = decode_cursor(cursor)
             stmt = stmt.where(
                 or_(
-                    ImageRecord.created_at < cur_ts,
-                    and_(ImageRecord.created_at == cur_ts, ImageRecord.id < cur_id),
+                    eff < cur_ts,
+                    and_(eff == cur_ts, ImageRecord.id < cur_id),
                 )
             )
 
-        stmt = stmt.order_by(ImageRecord.created_at.desc(), ImageRecord.id.desc()).limit(limit + 1)
-        rows = (await self.session.execute(stmt)).scalars().all()
+        stmt = stmt.order_by(eff.desc(), ImageRecord.id.desc()).limit(limit + 1)
+        rows = (await self.session.execute(stmt)).all()
 
         next_cursor = None
         if len(rows) > limit:
-            last = rows[limit - 1]
-            next_cursor = encode_cursor(last.created_at, last.id)
+            last_record, _last_posted_at, last_eff = rows[limit - 1]
+            next_cursor = encode_cursor(last_eff, last_record.id)
             rows = rows[:limit]
 
-        artists = await _artists_for(self.session, [r.id for r in rows])
+        artists = await _artists_for(
+            self.session, [r[0].id for r in rows]
+        )
         images = [
             GalleryImage(
-                id=r.id,
-                path=r.path,
-                sha256=r.sha256,
-                mime=r.mime,
-                width=r.width,
-                height=r.height,
-                created_at=r.created_at,
-                thumbnail_url=thumbnail_url(r.sha256, r.mime),
-                artist=artists.get(r.id),
+                id=record.id,
+                path=record.path,
+                sha256=record.sha256,
+                mime=record.mime,
+                width=record.width,
+                height=record.height,
+                created_at=record.created_at,
+                effective_date=eff_date,
+                posted_at=posted_at,
+                thumbnail_url=thumbnail_url(record.sha256, record.mime),
+                artist=artists.get(record.id),
             )
-            for r in rows
+            for record, posted_at, eff_date in rows
         ]
         return GalleryPage(
             images=images,
@@ -179,11 +215,13 @@ class GalleryService:
         post_id: int | None = None,
         artist_id: int | None = None,
     ) -> list[TimelineBucket]:
-        year_col = func.date_part("year", ImageRecord.created_at).label("yr")
-        month_col = func.date_part("month", ImageRecord.created_at).label("mo")
+        eff = _effective_date_col()
+        year_col = func.date_part("year", eff).label("yr")
+        month_col = func.date_part("month", eff).label("mo")
         stmt = select(
             year_col, month_col, func.count(ImageRecord.id).label("cnt")
         )
+        stmt = _outer_join_primary_post(stmt)
         _require_single_filter(tag_id, post_id, artist_id)
         if tag_id is not None:
             stmt = stmt.join(image_tag, image_tag.c.image_record_id == ImageRecord.id).where(
@@ -201,14 +239,17 @@ class GalleryService:
         post_id: int | None = None, artist_id: int | None = None,
     ) -> str | None:
         """Returns a cursor that, when passed to scroll(), positions at the
-        first image of the given year-month. None if the bucket is empty.
+        first image of the given year-month (by effective_date, not
+        created_at). None if the bucket is empty.
         """
         from sqlalchemy import extract
 
-        stmt = select(ImageRecord).where(
-            extract("year", ImageRecord.created_at) == year,
-            extract("month", ImageRecord.created_at) == month,
+        eff = _effective_date_col()
+        stmt = select(ImageRecord, eff.label("eff")).where(
+            extract("year", eff) == year,
+            extract("month", eff) == month,
         )
+        stmt = _outer_join_primary_post(stmt)
         _require_single_filter(tag_id, post_id, artist_id)
         if tag_id is not None:
             stmt = stmt.join(image_tag, image_tag.c.image_record_id == ImageRecord.id).where(
@@ -217,13 +258,14 @@ class GalleryService:
         prov = _provenance_clause(post_id, artist_id)
         if prov is not None:
             stmt = stmt.where(prov)
-        stmt = stmt.order_by(ImageRecord.created_at.desc(), ImageRecord.id.desc()).limit(1)
-        first = (await self.session.execute(stmt)).scalar_one_or_none()
+        stmt = stmt.order_by(eff.desc(), ImageRecord.id.desc()).limit(1)
+        first = (await self.session.execute(stmt)).first()
         if first is None:
             return None
+        record, eff_date = first
         # Cursor is exclusive; we encode a cursor with id+1 so the row itself
         # is the first result in the next scroll().
-        return encode_cursor(first.created_at, first.id + 1)
+        return encode_cursor(eff_date, record.id + 1)
 
     async def get_image_with_tags(self, image_id: int) -> dict | None:
         record = await self.session.get(ImageRecord, image_id)
@@ -236,6 +278,13 @@ class GalleryService:
             .order_by(Tag.kind.asc(), Tag.name.asc())
         )
         tags = (await self.session.execute(tag_stmt)).scalars().all()
+        # Fetch the canonical post.post_date for this image (if any) so
+        # the modal can show "Posted on <date>" alongside import date.
+        posted_at = None
+        if record.primary_post_id is not None:
+            posted_at = (await self.session.execute(
+                select(Post.post_date).where(Post.id == record.primary_post_id)
+            )).scalar_one_or_none()
         neighbors = await self._neighbors(record)
         # Direct artist FK — used by the modal's ProvenancePanel as a
         # fallback when ImageProvenance is empty (i.e., filesystem-
@@ -256,6 +305,7 @@ class GalleryService:
             "size_bytes": record.size_bytes,
             "integrity_status": record.integrity_status,
             "created_at": record.created_at.isoformat(),
+            "posted_at": posted_at.isoformat() if posted_at else None,
             "thumbnail_url": thumbnail_url(record.sha256, record.mime),
             "image_url": f"/images/{record.path.split('/images/', 1)[-1]}",
             "artist": (
@@ -275,34 +325,41 @@ class GalleryService:
         }
 
     async def _neighbors(self, record: ImageRecord) -> dict:
-        prev_stmt = (
-            select(ImageRecord.id)
-            .where(
+        # Compute the boundary image's effective_date in Python (one query
+        # below + the SELECT we already have on `record`) and use it for
+        # the neighbor comparison. Cheaper than re-deriving in SQL via
+        # correlated subquery.
+        boundary_eff = record.created_at
+        if record.primary_post_id is not None:
+            post_date = (await self.session.execute(
+                select(Post.post_date).where(Post.id == record.primary_post_id)
+            )).scalar_one_or_none()
+            if post_date is not None:
+                boundary_eff = post_date
+
+        eff = _effective_date_col()
+        prev_stmt = _outer_join_primary_post(
+            select(ImageRecord.id).where(
                 or_(
-                    ImageRecord.created_at > record.created_at,
+                    eff > boundary_eff,
                     and_(
-                        ImageRecord.created_at == record.created_at,
+                        eff == boundary_eff,
                         ImageRecord.id > record.id,
                     ),
                 )
             )
-            .order_by(ImageRecord.created_at.asc(), ImageRecord.id.asc())
-            .limit(1)
-        )
-        next_stmt = (
-            select(ImageRecord.id)
-            .where(
+        ).order_by(eff.asc(), ImageRecord.id.asc()).limit(1)
+        next_stmt = _outer_join_primary_post(
+            select(ImageRecord.id).where(
                 or_(
-                    ImageRecord.created_at < record.created_at,
+                    eff < boundary_eff,
                     and_(
-                        ImageRecord.created_at == record.created_at,
+                        eff == boundary_eff,
                         ImageRecord.id < record.id,
                     ),
                 )
             )
-            .order_by(ImageRecord.created_at.desc(), ImageRecord.id.desc())
-            .limit(1)
-        )
+        ).order_by(eff.desc(), ImageRecord.id.desc()).limit(1)
         prev_id = (await self.session.execute(prev_stmt)).scalar_one_or_none()
         next_id = (await self.session.execute(next_stmt)).scalar_one_or_none()
         return {"prev_id": prev_id, "next_id": next_id}
@@ -311,9 +368,11 @@ class GalleryService:
 def _group_by_year_month(
     images: list[GalleryImage],
 ) -> list[tuple[int, int, list[int]]]:
+    """Group by effective_date's year/month so migrated content surfaces
+    in the publish-date buckets, not the FC-scan-date bucket."""
     groups: list[tuple[int, int, list[int]]] = []
     for img in images:
-        y, m = img.created_at.year, img.created_at.month
+        y, m = img.effective_date.year, img.effective_date.month
         if groups and groups[-1][0] == y and groups[-1][1] == m:
             groups[-1][2].append(img.id)
         else:

backend/app/services/migrators/tag_apply.py

@@ -122,7 +122,14 @@ async def _ensure_provenance(
     db: AsyncSession, *,
     image_id: int, post_id: int, source_id: int, dry_run: bool,
 ) -> bool:
-    """Returns True if a new ImageProvenance row was inserted."""
+    """Returns True if a new ImageProvenance row was inserted.
+
+    Also sets ImageRecord.primary_post_id to this post if the image
+    doesn't already have one — preserves any primary_post_id already
+    assigned at download time by the importer (don't clobber). This is
+    the linkage gallery_service.py uses to surface Post.post_date as
+    the image's effective date for sort/group/jump/neighbor nav.
+    """
     existing = (await db.execute(
         select(ImageProvenance.id).where(
             ImageProvenance.image_record_id == image_id,
@@ -130,6 +137,18 @@ async def _ensure_provenance(
             ImageProvenance.source_id == source_id,
         )
     )).scalar_one_or_none()
+
+    # Whether-or-not the provenance row already exists, ensure the
+    # image's primary_post_id is set so the gallery date-coalesce works.
+    # Idempotent: only writes when currently NULL.
+    if not dry_run:
+        await db.execute(
+            ImageRecord.__table__.update()
+            .where(ImageRecord.id == image_id)
+            .where(ImageRecord.primary_post_id.is_(None))
+            .values(primary_post_id=post_id)
+        )
+
     if existing is not None:
         return False
     if dry_run:

tests/test_gallery_service.py

@@ -133,3 +133,135 @@ async def test_get_image_with_tags_includes_integrity_status(db):
     svc = GalleryService(db)
     payload = await svc.get_image_with_tags(img.id)
     assert payload["integrity_status"] == "ok"
+
+
+async def _seed_image_with_post(
+    db, *, sha: str, image_created_at, post_date, artist_name="test-artist",
+    platform="patreon", external_post_id="42",
+):
+    """Helper: seed an Artist + Source + Post and one ImageRecord whose
+    primary_post_id points at that Post. Used for date-coalesce tests."""
+    from backend.app.models import Artist, Post, Source
+    artist = Artist(name=artist_name, slug=artist_name.lower().replace(" ", "-"))
+    db.add(artist)
+    await db.flush()
+    source = Source(
+        artist_id=artist.id, platform=platform,
+        url=f"https://www.{platform}.com/{artist.slug}",
+    )
+    db.add(source)
+    await db.flush()
+    post = Post(
+        source_id=source.id, external_post_id=external_post_id,
+        post_title="A Post", post_date=post_date,
+    )
+    db.add(post)
+    await db.flush()
+    img = ImageRecord(
+        path=f"/images/test/{sha[:8]}.jpg",
+        sha256=sha, size_bytes=1000, mime="image/jpeg",
+        width=100, height=100,
+        origin="imported_filesystem", integrity_status="unknown",
+        primary_post_id=post.id,
+    )
+    img.created_at = image_created_at
+    db.add(img)
+    await db.flush()
+    return img, post
+
+
+@pytest.mark.asyncio
+async def test_scroll_sorts_by_post_date_when_available(db):
+    """Operator-flagged 2026-05-25: ~57k IR images all imported in the
+    same week sort by image.created_at and pile up in one month bucket.
+    Once primary_post_id is wired (via tag_apply phase 4), the gallery
+    should sort by Post.post_date instead, spreading them across the
+    actual publish years."""
+    base_import = _now()
+    # Image A: imported NOW, but post was made 2 years ago.
+    img_a, _ = await _seed_image_with_post(
+        db, sha="a" * 64,
+        image_created_at=base_import,
+        post_date=base_import - timedelta(days=730),
+        artist_name="Aria", external_post_id="A-1",
+    )
+    # Image B: imported NOW (1 min later), post made YESTERDAY.
+    img_b, _ = await _seed_image_with_post(
+        db, sha="b" * 64,
+        image_created_at=base_import - timedelta(minutes=1),
+        post_date=base_import - timedelta(days=1),
+        artist_name="Bea", external_post_id="B-1",
+    )
+    # Image C: filesystem-imported, no primary_post_id, created 5 days ago.
+    img_c = ImageRecord(
+        path="/images/test/c.jpg", sha256="c" * 64,
+        size_bytes=1000, mime="image/jpeg",
+        width=100, height=100,
+        origin="imported_filesystem", integrity_status="unknown",
+    )
+    img_c.created_at = base_import - timedelta(days=5)
+    db.add(img_c)
+    await db.flush()
+
+    svc = GalleryService(db)
+    page = await svc.scroll(cursor=None, limit=10)
+    # Effective-date order: B (yesterday) > C (5 days ago) > A (2 years ago)
+    assert [i.id for i in page.images] == [img_b.id, img_c.id, img_a.id]
+
+    # API exposes both fields explicitly so the UI can show "Posted X / Imported Y".
+    a_payload = next(i for i in page.images if i.id == img_a.id)
+    assert a_payload.posted_at is not None
+    assert a_payload.posted_at < a_payload.created_at
+    c_payload = next(i for i in page.images if i.id == img_c.id)
+    assert c_payload.posted_at is None
+    assert c_payload.effective_date == c_payload.created_at
+
+
+@pytest.mark.asyncio
+async def test_timeline_buckets_use_post_date_when_available(db):
+    """Timeline group-by must follow the same effective_date rule so the
+    UI's year/month navigation surfaces publish-date buckets, not the
+    single FC-scan bucket all migrated images share."""
+    base = datetime(2026, 6, 15, 12, 0, tzinfo=UTC)
+    await _seed_image_with_post(
+        db, sha="1" * 64,
+        image_created_at=base,
+        post_date=datetime(2024, 3, 10, tzinfo=UTC),
+        artist_name="Carl", external_post_id="C-1",
+    )
+    await _seed_image_with_post(
+        db, sha="2" * 64,
+        image_created_at=base,
+        post_date=datetime(2024, 3, 11, tzinfo=UTC),
+        artist_name="Dee", external_post_id="D-1",
+    )
+    await _seed_image_with_post(
+        db, sha="3" * 64,
+        image_created_at=base,
+        post_date=datetime(2025, 9, 1, tzinfo=UTC),
+        artist_name="Eli", external_post_id="E-1",
+    )
+    svc = GalleryService(db)
+    buckets = await svc.timeline()
+    bucket_keys = {(b.year, b.month, b.count) for b in buckets}
+    # Two posts in 2024-03, one in 2025-09 — even though all imported in 2026-06.
+    assert (2024, 3, 2) in bucket_keys
+    assert (2025, 9, 1) in bucket_keys
+    # The FC-import bucket should NOT appear since all 3 images have post_date.
+    assert not any(b.year == 2026 and b.month == 6 for b in buckets)
+
+
+@pytest.mark.asyncio
+async def test_get_image_with_tags_includes_posted_at_when_present(db):
+    base = _now()
+    img, _ = await _seed_image_with_post(
+        db, sha="f" * 64,
+        image_created_at=base,
+        post_date=base - timedelta(days=365),
+        artist_name="Fred", external_post_id="F-1",
+    )
+    svc = GalleryService(db)
+    payload = await svc.get_image_with_tags(img.id)
+    assert payload["posted_at"] is not None
+    # Image's own created_at is still surfaced separately.
+    assert payload["created_at"] != payload["posted_at"]

tests/test_tag_apply.py

@@ -227,6 +227,67 @@ async def test_image_posts_creates_source_post_provenance(db, tmp_path):
     )).scalar_one()
     assert prov_count == 1
 
+    # Phase 4 must also set ImageRecord.primary_post_id so the gallery's
+    # effective_date COALESCE can surface Post.post_date. Operator-flagged
+    # 2026-05-25: without this, IR-migrated images keep sorting by FC's
+    # scan date instead of the original publish date.
+    primary_post_id = (await db.execute(
+        select(ImageRecord.primary_post_id).where(ImageRecord.id == img_id)
+    )).scalar_one()
+    canonical_post_id = (await db.execute(
+        select(Post.id).where(Post.external_post_id == "10001")
+    )).scalar_one()
+    assert primary_post_id == canonical_post_id
+
+
+@pytest.mark.asyncio
+async def test_image_posts_primary_post_id_not_clobbered(db, tmp_path):
+    """If the importer already set primary_post_id (e.g. a downloaded
+    image with a known provenance), phase 4 must NOT overwrite it when
+    re-running tag_apply against the IR migration. The existing
+    download-time linkage is the source of truth."""
+    sha = "9" * 64
+    await _seed_image(db, sha, suffix="9")
+    # Pre-set primary_post_id to a sentinel Post so we can detect a clobber.
+    img_id = (await db.execute(
+        select(ImageRecord.id).where(ImageRecord.sha256 == sha)
+    )).scalar_one()
+    # Build an existing Source + Post for the sentinel.
+    art = Artist(name="Pre-existing", slug="pre-existing")
+    db.add(art)
+    await db.flush()
+    src = Source(
+        artist_id=art.id, platform="patreon",
+        url="https://www.patreon.com/pre-existing",
+    )
+    db.add(src)
+    await db.flush()
+    sentinel_post = Post(
+        source_id=src.id, external_post_id="sentinel-99",
+        post_title="Pre-existing",
+    )
+    db.add(sentinel_post)
+    await db.flush()
+    await db.execute(
+        ImageRecord.__table__.update()
+        .where(ImageRecord.id == img_id)
+        .values(primary_post_id=sentinel_post.id)
+    )
+    await db.commit()
+
+    _write_manifest(tmp_path, image_posts=[
+        {**_POST_ENTRY, "image_sha256s": [sha]},
+    ])
+    await tag_apply.apply_async(db, images_root=tmp_path, dry_run=False)
+
+    # The migration created a NEW Post (external_post_id="10001") and a
+    # new ImageProvenance, but primary_post_id must still point at the
+    # original sentinel.
+    primary_post_id = (await db.execute(
+        select(ImageRecord.primary_post_id).where(ImageRecord.id == img_id)
+    )).scalar_one()
+    assert primary_post_id == sentinel_post.id
+
 
 @pytest.mark.asyncio
 async def test_image_posts_idempotent_on_rerun(db, tmp_path):