diff --git a/CLAUDE.md b/CLAUDE.md
index 8df147c..3644750 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -95,6 +95,43 @@ Turning a region back into slices re-derives, per cell, the same filters Perspec
---
+## Column hierarchy (collapse / expand)
+
+The two pivot axes collapse by completely different mechanisms, and the asymmetry is a
+Perspective constraint, not a choice:
+
+- **Rows.** The `GROUP BY ROLLUP` view holds every level at once; `view.set_depth()` — which
+ lives on the view, not the config — hides the deeper ones. That is what the `EXPAND 0 1 2 3`
+ buttons drive, via `applyDepth()`.
+- **Columns.** There is no equivalent. `expand()` / `collapse()` take a **row index**,
+ `ViewConfig` has `group_by_depth` but no `split_by_depth`, and `split_rollup_mode`
+ (`'flat' | 'rollup'`) only chooses whether subtotal column groups are *emitted* — it is a
+ view shape, not an interaction. So `applySplitDepth(n)` collapses by restoring a
+ **truncated `split_by`**, which rebuilds the view.
+
+Three things follow from the rebuild, and each is handled:
+
+1. The full hierarchy has to be remembered separately — once collapsed, `viewer.save()`
+ only reports the short `split_by`. `splitFullRef` / `splitFull` hold it, and it is
+ persisted into the saved layout as `split_full` so a reload while collapsed can still
+ expand back. `adoptSplit()` is the single place it is set.
+2. `perspective-config-update` fires for our own restore as well as the user rearranging
+ the pivot. `collapsingRef` distinguishes them — without it, a collapse would overwrite
+ the full hierarchy with the truncated one and the deeper levels would be unreachable.
+3. Row depth lives on the discarded view, so `applyDepth(expandDepthRef.current)` is
+ re-applied afterwards — the same wart as the refocus re-apply.
+
+The selection is cleared on every change: slices name the split_by dimensions they were
+cut from, and the highlight is keyed on grid coordinates. Neither survives a column axis
+that just changed shape.
+
+**Limitation:** this is whole-axis, not per-branch. Excel can collapse 2025 while 2026
+stays expanded; truncating `split_by` collapses every column group at that level together.
+Per-branch is not reachable — `columns` selects which *measures* appear, not individual
+split combinations.
+
+---
+
## Operation SQL patterns
All three operations follow the same structure: insert a `pf.log` row in a CTE, then insert forecast rows referencing its id. `{{where_clause}}` is built from the slice; `{{exclude_clause}}` blocks `exclude_iters` rows.
diff --git a/ui/src/views/Forecast.jsx b/ui/src/views/Forecast.jsx
index 648586b..46fe05a 100644
--- a/ui/src/views/Forecast.jsx
+++ b/ui/src/views/Forecast.jsx
@@ -23,6 +23,8 @@ function cleanLayout(cfg, validCols) {
if (c.columns) c.columns = c.columns.filter(col => col == null || ok(col))
if (c.group_by) c.group_by = c.group_by.filter(ok)
if (c.split_by) c.split_by = c.split_by.filter(ok)
+ // the uncollapsed column hierarchy travels with the layout (see applySplitDepth)
+ if (c.split_full) c.split_full = c.split_full.filter(ok)
if (c.sort) c.sort = c.sort.filter(([col]) => ok(col))
if (c.filter) c.filter = c.filter.filter(([col]) => ok(col))
return c
@@ -42,6 +44,12 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
const [saveAsName, setSaveAsName] = useState('')
// operation panel — a selection is a LIST of slices; one entry is the common case
+ // The column hierarchy and how many of its levels are showing. Mirrored into
+ // splitFullRef for handlers registered once; held as state so the toolbar
+ // re-renders when either changes.
+ const [splitFull, setSplitFull] = useState([])
+ const [splitDepth, setSplitDepth] = useState(null)
+
const [slices, setSlices] = useState([])
const [applyMode, setApplyMode] = useState('prorate') // 'prorate' | 'each'
const [activeOp, setActiveOp] = useState('scale')
@@ -167,6 +175,12 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
const tableRef = useRef(null)
const colMetaRef = useRef([])
const expandDepthRef = useRef(null)
+ // The column axis has no set_depth() — collapsing it means restoring a shorter
+ // split_by, so the full hierarchy has to be remembered separately to expand again.
+ const splitFullRef = useRef([])
+ // set while our own restore is in flight, so the config-update listener can tell
+ // a collapse from the user rearranging split_by themselves
+ const collapsingRef = useRef(false)
const initIdRef = useRef(0)
const modifierRef = useRef(false)
// the datagrid plugin element, for reading cell coordinates and driving its
@@ -536,6 +550,7 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
setLoadProgress(null)
setSlices([])
expandDepthRef.current = null
+ adoptSplit([], 0)
try {
const [dataResult, meta] = await Promise.all([
fetch(`/api/versions/${vid}/data`).then(async r => {
@@ -616,6 +631,9 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
const { table: _t, ...rest } = cleanLayout(JSON.parse(saved), validCols)
const cfg = { ...rest, plugin_config: { ...(rest.plugin_config || {}), edit_mode: 'SELECT_REGION' } }
await viewer.restore(cfg)
+ // split_full outlives split_by: a layout saved while collapsed still knows
+ // the levels it was collapsed from
+ adoptSplit(cfg.split_full?.length ? cfg.split_full : cfg.split_by, (cfg.split_by || []).length)
if (cfg.expand_depth != null) await applyDepth(cfg.expand_depth)
} else {
const sourceDefault = sources.find(s => String(s.id) === String(sid))?.default_layout
@@ -633,12 +651,19 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
}
}
await viewer.restore(cfg)
+ adoptSplit(cfg.split_full?.length ? cfg.split_full : cfg.split_by, (cfg.split_by || []).length)
}
// auto-persist viewer state (formatting, columns, etc.) to the last-used cache
if (viewer._pspUpdate) viewer.removeEventListener('perspective-config-update', viewer._pspUpdate)
viewer._pspUpdate = async () => {
try {
+ // A split_by change that is not ours is the user rearranging the pivot, and
+ // it redefines the hierarchy. Ours is a collapse, and must not overwrite it.
+ if (!collapsingRef.current) {
+ const live = await viewer.save()
+ adoptSplit(live.split_by || [], (live.split_by || []).length)
+ }
const cfg = await captureConfig()
if (cfg) await persistLayout(vid, cfg)
} catch {}
@@ -690,6 +715,54 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
}
}
+ // Record the column hierarchy as the uncollapsed truth. Called whenever a layout
+ // arrives or the user rearranges split_by themselves — but never for our own
+ // collapse, which would otherwise overwrite the full list with the short one.
+ function adoptSplit(full, depth) {
+ const list = Array.isArray(full) ? full : []
+ splitFullRef.current = list
+ setSplitFull(list)
+ setSplitDepth(depth == null ? list.length : Math.min(depth, list.length))
+ }
+
+ // Collapse or expand the column axis to `n` split_by levels.
+ //
+ // The row axis gets this for free: its GROUP BY ROLLUP view holds every level at
+ // once and view.set_depth() hides the deeper ones. The column axis has no
+ // equivalent — there is no split_by_depth in ViewConfig and expand()/collapse()
+ // take a row index — so collapsing means restoring a truncated split_by, which
+ // rebuilds the view. Two consequences fall out of that: the row depth has to be
+ // re-applied afterwards (it lives on the discarded view), and it is whole-axis,
+ // not per-branch — every column group collapses to the same level together.
+ async function applySplitDepth(n) {
+ const viewer = viewerRef.current
+ const full = splitFullRef.current
+ if (!viewer || !full.length) return
+ const depth = Math.max(0, Math.min(n, full.length))
+ collapsingRef.current = true
+ try {
+ await viewer.restore({ split_by: full.slice(0, depth) })
+ setSplitDepth(depth)
+ // restore() rebuilt the view, so the row depth that lived on the old one is gone
+ if (expandDepthRef.current != null) await applyDepth(expandDepthRef.current)
+ } catch (err) {
+ console.error('[applySplitDepth]', err)
+ flash(err.message || String(err), 'error')
+ return
+ } finally {
+ collapsingRef.current = false
+ }
+ // a slice names the split_by dimensions it was cut from, and the highlight is
+ // keyed on grid coordinates — neither survives a column axis that just changed
+ setSlices([])
+ try {
+ const cfg = await captureConfig()
+ if (cfg) await persistLayout(versionId, cfg)
+ } catch (err) {
+ console.error('[applySplitDepth persist]', err)
+ }
+ }
+
async function applyDepth(d) {
const viewer = viewerRef.current
if (!viewer) return
@@ -704,7 +777,7 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
const viewer = viewerRef.current
if (!viewer) return null
const cfg = await viewer.save()
- return { ...cfg, expand_depth: expandDepthRef.current }
+ return { ...cfg, expand_depth: expandDepthRef.current, split_full: splitFullRef.current }
}
async function persistLayout(vid, cfg) {
@@ -762,6 +835,7 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
const cfg = cleanLayout(layout.config, validCols)
cfg.plugin_config = { ...(cfg.plugin_config || {}), edit_mode: 'SELECT_REGION' }
await viewer.restore(cfg)
+ adoptSplit(cfg.split_full?.length ? cfg.split_full : cfg.split_by, (cfg.split_by || []).length)
if (cfg.expand_depth != null) await applyDepth(cfg.expand_depth)
setActiveLayoutId(layout.id)
await persistLayout(versionId, cfg)
@@ -1087,6 +1161,30 @@ export default function Forecast({ sources = [], sourceId, versions = [], versio
))}
+ {splitFull.length > 0 && (
+ <>
+
+
+ {/* Column hierarchy group — the split_by equivalent of Expand */}
+