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diff --git a/‎packages/services/service-analytics/src/__tests__/objectql-echo-offset-only-window.test.ts‎
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diff --git a/‎packages/services/service-analytics/src/strategies/objectql-strategy.ts‎
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@@ -0,0 +1,13 @@
+---
+"@objectstack/service-analytics": patch
+---
+
+fix(service-analytics): the ObjectQL strategy's echoed `sql` renders an offset with no limit in the dialect's own spelling, so SQLite runs the statement it prints
+
+Clause-②: no
+
+**Before**, the ObjectQL strategy wrote its own row window into the statement it echoes: `LIMIT n` when a limit was set, then `OFFSET n` when an offset was. An `offset` with no `limit` therefore echoed a bare `OFFSET`, which SQLite's grammar does not have. Measured through `POST /api/v1/analytics/query` and `POST /api/v1/analytics/sql` on SQLite, for a composition served by the engine aggregate, with `order: { note: 'asc' }` and `offset: 1`: the rows were right (every group after the first), but the echoed `sql` and the `/analytics/sql` body both ended `ORDER BY "note" ASC OFFSET 1`, and SQLite refuses that statement with `near "OFFSET": syntax error`.
+
+**Now** the statement ends with the same window clause the native-SQL strategy runs, for the dialect of the driver that serves the object: `LIMIT -1 OFFSET 1` on SQLite, which runs and answers the same rows. One function renders the window for both strategies.
+
+**Unchanged.** The rows either strategy answers. A window with a `limit` keeps its bytes (`LIMIT 2 OFFSET 1`) on every dialect, and on PostgreSQL an offset with no limit still echoes `OFFSET 1` alone. A host that wires no `sqlDialect` hook gets the native strategy's dialect-neutral spelling, `LIMIT 9223372036854775807 OFFSET 1`. A date-bucketed dimension still echoes as `date_trunc(…)`, which SQLite does not run; this change touches only the window.
@@ -0,0 +1,240 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * [#21365] The ObjectQL face echoes an offset-only window as a statement the
+ * dialect runs: the same window clause the native face executes.
+ *
+ * ## The shape this closes
+ *
+ * `ObjectQLStrategy.generateSql` wrote its own window: `LIMIT n` when a limit
+ * was set, then `OFFSET n` when an offset was. An offset with no limit
+ * therefore echoed a bare `OFFSET`. Measured at `POST /api/v1/analytics/query`
+ * and `POST /api/v1/analytics/sql` on `main` `bdd3654f2`, SQLite, a
+ * composition narrowed to the engine aggregate, `order { note: 'asc' }`,
+ * `offset: 1`:
+ *
+ * | | rows | echoed `sql` and `/analytics/sql` | that statement on SQLite |
+ * |:--|:--|:--|:--|
+ * | ObjectQL face | x y z | `… ORDER BY "note" ASC OFFSET 1` | `near "OFFSET": syntax error` |
+ * | native face | x y z | `… ORDER BY "note" ASC LIMIT -1 OFFSET 1` (what ran) | x y z |
+ *
+ * The rows were right; the statement the face printed for them was one SQLite
+ * refuses. `generateSql` now ends with `windowClauseSql` (exported from
+ * `native-sql-strategy.ts`, not a second spelling table) for the dialect the
+ * `sqlDialect` hook names for the base object, so both faces print one window.
+ *
+ * ## The cells
+ *
+ *   - **sqlite → EXECUTED** (better-sqlite3), every run.
+ *   - **postgres → EXECUTED** where `OS_TEST_POSTGRES_URL` is set, a named skip
+ *     otherwise: `OFFSET n` alone, byte-identical to before. No CI step
+ *     provisions that variable for this package, so the live cell is
+ *     red-capable and un-run in CI.
+ *   - **unknown (no `sqlDialect` hook) → EXECUTED** on both engines above,
+ *     through an `ObjectQLStrategy` whose context names no dialect:
+ *     `LIMIT 9223372036854775807 OFFSET n`, the native face's spelling for it.
+ *
+ * In each cell the echo's window is compared with the statement the native
+ * face runs for the same query on the same driver, and the echo is then run
+ * itself through the engine's raw-SQL bridge, where it must answer the face's
+ * rows.
+ */
+
+import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import { ObjectQL } from '@objectstack/objectql';
+import { SqlDriver } from '@objectstack/driver-sql';
+import type { Cube } from '@objectstack/spec/data';
+import type { AnalyticsService } from '../analytics-service.js';
+import { AnalyticsServicePlugin } from '../plugin.js';
+import { ObjectQLStrategy } from '../strategies/objectql-strategy.js';
+import type { StrategyContext } from '../strategies/types.js';
+
+const DEAL = 'os21365_echo_deal';
+
+const DEAL_OBJECT = {
+  name: DEAL,
+  label: 'Offset echo deal',
+  fields: {
+    note: { name: 'note', type: 'text' as const },
+    amount: { name: 'amount', type: 'number' as const },
+  },
+};
+
+// Inserted out of note order, so an answer in note order is the ORDER BY's.
+const DEALS = [
+  { id: 'd1', note: 'y', amount: 20 },
+  { id: 'd2', note: 'w', amount: 7 },
+  { id: 'd3', note: 'z', amount: 1 },
+  { id: 'd4', note: 'x', amount: 10 },
+  { id: 'd5', note: 'x', amount: 5 },
+] as const;
+
+const CUBE = 'os21365_echo_cube';
+const CUBES = [
+  {
+    name: CUBE,
+    title: 'Offset echo cube',
+    sql: DEAL,
+    public: true,
+    measures: { amount_sum: { type: 'sum', sql: 'amount', label: 'Amount' } },
+    dimensions: { note: { type: 'string', sql: 'note', label: 'Note' } },
+  },
+] as unknown as Cube[];
+
+/** The card's row 4: ordered, an offset, no limit. */
+const OFFSET_ONLY = { cube: CUBE, measures: ['amount_sum'], dimensions: ['note'], order: { note: 'asc' }, offset: 1 };
+/** Every group after the first, in note order. */
+const AFTER_FIRST = [['x', 15], ['y', 20], ['z', 1]];
+
+interface Cell {
+  id: 'sqlite' | 'pg';
+  label: string;
+  env: string | null;
+  config: () => Record<string, unknown> | null;
+  /** The no-limit spelling the dialect takes in front of `OFFSET`, `''` for none. */
+  noLimit: string;
+}
+
+const CELLS: readonly Cell[] = [
+  {
+    id: 'sqlite',
+    label: 'sqlite',
+    env: null,
+    config: () => ({ client: 'better-sqlite3', connection: { filename: ':memory:' }, useNullAsDefault: true }),
+    noLimit: ' LIMIT -1',
+  },
+  {
+    id: 'pg',
+    label: 'live postgres',
+    env: 'OS_TEST_POSTGRES_URL',
+    config: () => (process.env.OS_TEST_POSTGRES_URL ? { client: 'pg', connection: process.env.OS_TEST_POSTGRES_URL } : null),
+    noLimit: '',
+  },
+];
+
+const FACES = ['native', 'objectql'] as const;
+type Face = (typeof FACES)[number];
+
+const quiet = { debug() {}, info() {}, warn() {}, error() {}, child() { return quiet; } };
+
+type Row = Record<string, unknown>;
+
+/** Rows as tuples of the named columns, in arrival order; a numeric cell reads as a number on every dialect. */
+const tuples = (rows: unknown, columns: readonly string[]) =>
+  (rows as Row[]).map((row) => columns.map((c) => (typeof row[c] === 'number' || /^-?\d+(\.\d+)?$/.test(String(row[c])) ? Number(row[c]) : row[c])));
+
+for (const cell of CELLS) {
+  const config = cell.config();
+  describe.skipIf(!config)(
+    `[#21365] the ObjectQL face echoes an offset-only window the dialect runs (${cell.label})${config ? '' : ` (skipped: set ${cell.env} to run this cell)`}`,
+    () => {
+      let driver: any;
+      let engine: ObjectQL;
+      /** Every raw statement the engine ran, in order. */
+      const executed: string[] = [];
+      const reads = { aggregate: 0 };
+      const services: Partial<Record<Face, AnalyticsService>> = {};
+
+      const dropTables = async () => {
+        if (cell.id !== 'pg') return;
+        await driver?.execute(`drop table if exists ${DEAL}`).catch(() => {});
+      };
+
+      /** One `query()` on one face, with the statements and aggregates it caused. */
+      const ask = async (face: Face, query: Record<string, unknown>) => {
+        const before = { statements: executed.length, aggregate: reads.aggregate };
+        const res = await services[face]!.query(query as any);
+        return { res, statements: executed.slice(before.statements), aggregate: reads.aggregate - before.aggregate };
+      };
+
+      /** Run a statement through the engine's raw-SQL bridge, as the native face does. */
+      const run = async (sql: string) => {
+        const result = await (engine as any).execute(sql, { object: DEAL });
+        return Array.isArray(result) ? result : (result as { rows: Row[] }).rows;
+      };
+
+      beforeAll(async () => {
+        driver = new SqlDriver(config as any);
+        await dropTables();
+        engine = new ObjectQL({ logger: quiet } as any);
+        engine.registerDriver(driver, true);
+        await engine.init();
+        engine.registry.registerObject(DEAL_OBJECT as any);
+        await engine.syncSchemas();
+        for (const row of DEALS) await engine.insert(DEAL, { ...row } as any);
+
+        const realExecute = (engine as any).execute.bind(engine);
+        (engine as any).execute = (sql: unknown, opts?: unknown) => {
+          executed.push(String(sql));
+          return realExecute(sql, opts);
+        };
+        const realAggregate = engine.aggregate.bind(engine);
+        (engine as any).aggregate = (...args: unknown[]) => {
+          reads.aggregate += 1;
+          return (realAggregate as any)(...args);
+        };
+
+        for (const [face, caps] of [
+          ['native', undefined],
+          ['objectql', () => ({ nativeSql: false, objectqlAggregate: true, inMemory: false })],
+        ] as const) {
+          const registered: Record<string, unknown> = {};
+          await new AnalyticsServicePlugin({ cubes: CUBES, debugSql: true, ...(caps ? { queryCapabilities: caps } : {}) } as any).init({
+            getService: (name: string) => (name === 'data' ? engine : registered[name]),
+            registerService: (name: string, svc: unknown) => { registered[name] = svc; },
+            replaceService: (name: string, svc: unknown) => { registered[name] = svc; },
+            hook: () => {},
+            logger: quiet,
+          } as never);
+          services[face] = registered.analytics as AnalyticsService;
+        }
+      });
+
+      afterAll(async () => {
+        await dropTables();
+        try { await engine?.destroy(); } catch { /* noop */ }
+      });
+
+      it("the card's row — ordered, offset 1, no limit: the echo and /analytics/sql carry the dialect's window, and it runs", async () => {
+        const objectql = await ask('objectql', OFFSET_ONLY);
+        expect(objectql.statements, 'the ObjectQL face ran no raw statement').toEqual([]);
+        expect(objectql.aggregate, 'the ObjectQL face ran the engine aggregate').toBeGreaterThan(0);
+        expect(tuples(objectql.res.rows, ['note', 'amount_sum']), 'ObjectQL face').toEqual(AFTER_FIRST);
+
+        const echo = objectql.res.sql!;
+        expect(echo.endsWith(`ORDER BY "note" ASC${cell.noLimit} OFFSET 1`), echo).toBe(true);
+        // `generateSql` is the body `POST /analytics/sql` answers with.
+        const dryRun = await services.objectql!.generateSql!(OFFSET_ONLY as any);
+        expect(dryRun.sql).toBe(echo);
+
+        // The window the native face runs for the same query on the same driver.
+        // Compared from `ORDER BY` on: on PostgreSQL the native face also casts
+        // the summed column, so the two statements differ before it.
+        const native = await ask('native', OFFSET_ONLY);
+        expect(native.statements, 'the native face ran ONE statement').toHaveLength(1);
+        const fromOrderBy = (sql: string) => sql.slice(sql.indexOf(' ORDER BY '));
+        expect(fromOrderBy(echo)).toBe(fromOrderBy(native.statements[0]));
+
+        // The echo binds no parameter, so it runs as printed — and answers the face's rows.
+        expect(dryRun.params).toEqual([]);
+        expect(tuples(await run(echo), ['note', 'amount_sum'])).toEqual(AFTER_FIRST);
+      });
+
+      it('a host that wires no sqlDialect hook (the `unknown` arm) echoes the dialect-neutral window, and it runs', async () => {
+        const ctx = { getCube: (name: string) => (name === CUBE ? CUBES[0] : undefined) } as unknown as StrategyContext;
+        const { sql, params } = await new ObjectQLStrategy().generateSql(OFFSET_ONLY as any, ctx);
+        expect(sql.endsWith('ORDER BY "note" ASC LIMIT 9223372036854775807 OFFSET 1'), sql).toBe(true);
+        expect(params).toEqual([]);
+        expect(tuples(await run(sql), ['note', 'amount_sum'])).toEqual(AFTER_FIRST);
+      });
+
+      it('CONTROL: an integer window keeps its bytes — `LIMIT 2 OFFSET 1` — and the echo runs', async () => {
+        const query = { ...OFFSET_ONLY, limit: 2 };
+        const { res } = await ask('objectql', query);
+        expect(res.sql!.endsWith('ORDER BY "note" ASC LIMIT 2 OFFSET 1'), res.sql).toBe(true);
+        expect(tuples(res.rows, ['note', 'amount_sum'])).toEqual([['x', 15], ['y', 20]]);
+        expect(tuples(await run(res.sql!), ['note', 'amount_sum'])).toEqual([['x', 15], ['y', 20]]);
+      });
+    },
+  );
+}
@@ -48,7 +48,9 @@ import {
 // [commit 017130a09] The custom-SQL half of the `AggregationMetricType` partition, ONE
 // source shared with `NativeSQLStrategy` and pinned against the spec enum by
 // `metric-type-coverage.test.ts` — a second literal set here would drift.
-import { EXPRESSION_METRIC_TYPES } from './native-sql-strategy.js';
+// [#21365] `windowClauseSql` is the same rule for the row window: one spelling
+// of an offset-only window per dialect, shared with the native face.
+import { EXPRESSION_METRIC_TYPES, windowClauseSql } from './native-sql-strategy.js';
 
 /**
  * [#10861 / commit 399ecad58] Where a member in the cross-object envelope's inventory
@@ -673,8 +675,13 @@ export class ObjectQLStrategy implements AnalyticsStrategy {
       const orderClauses = Object.entries(query.order).map(([f, d]) => `"${f}" ${d.toUpperCase()}`);
       sql += ` ORDER BY ${orderClauses.join(', ')}`;
     }
-    if (query.limit != null) sql += ` LIMIT ${query.limit}`;
-    if (query.offset != null) sql += ` OFFSET ${query.offset}`;
+    // [#21365] The window renders through the native face's own
+    // `windowClauseSql`, for the dialect of the driver the engine aggregate
+    // runs on — the same `sqlDialect` read the read scope above makes. An
+    // offset with no limit then carries that dialect's no-limit spelling
+    // (`LIMIT -1 OFFSET n` on SQLite, whose grammar has no bare `OFFSET`), so
+    // the echoed `sql` and `/analytics/sql` print a window the dialect runs.
+    sql += windowClauseSql(query.limit, query.offset, sqlDialectFor(ctx, tableName));
 
     return { sql, params };
   }