diff --git a/docs/data.md b/docs/data.md
index 7523f8b..38f20e8 100644
--- a/docs/data.md
+++ b/docs/data.md
@@ -206,7 +206,7 @@ Test-only exports `_resetCache()` and `_cacheSize()` allow test isolation.
 
 The optional `filter` callback enables pre-filtering JSONL rows (used by `test-run` to keep only `type === 'result'` events). Old all-events schema is detected by the presence of a `message` column and auto-migrated by deleting and rebuilding.
 
-`updateAllParquet()` orchestrates import for eight tables: `test-config`, `test-run`, `test-results`, `output-files`, `scil-iteration`, `scil-summary`, `acil-iteration`, and `acil-summary`. SCIL and ACIL summaries each require a special step that converts per-run `.json` files to a temp JSONL before import.
+`updateAllParquet()` orchestrates import for eight tables: `test-config`, `test-run`, `test-results`, `output-files`, `scil-iteration`, `scil-summary`, `acil-iteration`, and `acil-summary`. SCIL and ACIL summaries each require a special step that converts per-run `.json` files to a temp JSONL before import. It creates the data directory first if it does not exist, since DuckDB's `COPY ... TO` will not create parent directories.
 
 ### Analytics Queries (`analytics.ts`, `run-status.ts`)
 
diff --git a/packages/data/src/analytics.integration.test.ts b/packages/data/src/analytics.integration.test.ts
index 47d019b..e659d57 100644
--- a/packages/data/src/analytics.integration.test.ts
+++ b/packages/data/src/analytics.integration.test.ts
@@ -205,6 +205,17 @@ describe('updateAllParquet', () => {
     expect(rows.every((r) => r.type === 'result')).toBe(true)
   })
 
+  it('creates the data directory when it does not exist yet', async () => {
+    const outputDir = path.join(tmpDir, 'output')
+    const dataDir = path.join(tmpDir, 'analytics')
+    await writeRunFixture({ outputDir, testRunId: '20260101T100001', eval: 's', testName: 't' })
+
+    const { updated } = await updateAllParquet({ outputDir, dataDir })
+
+    expect(updated).toEqual(expect.arrayContaining(['test-config', 'test-run', 'test-results']))
+    expect(existsSync(path.join(dataDir, 'test-config.parquet'))).toBe(true)
+  })
+
   it('returns empty updated list when no JSONL files exist', async () => {
     const outputDir = path.join(tmpDir, 'output-empty')
     const dataDir = path.join(tmpDir, 'analytics')
diff --git a/packages/data/src/analytics.ts b/packages/data/src/analytics.ts
index c742ce8..add6dca 100644
--- a/packages/data/src/analytics.ts
+++ b/packages/data/src/analytics.ts
@@ -1,6 +1,6 @@
 import crypto from 'node:crypto'
 import { existsSync } from 'node:fs'
-import { readdir, readFile, rename, unlink, writeFile } from 'node:fs/promises'
+import { mkdir, readdir, readFile, rename, unlink, writeFile } from 'node:fs/promises'
 import os from 'node:os'
 import path from 'node:path'
 import { type DuckDBConnection, DuckDBInstance } from '@duckdb/node-api'
@@ -165,6 +165,8 @@ export async function updateAllParquet({
     { name: 'output-files', glob: `${outputDir}/*/output-files.jsonl`, parquet: `${dataDir}/output-files.parquet` },
   ]
 
+  await mkdir(dataDir, { recursive: true })
+
   const updated: string[] = []
 
   for (const table of tables) {