order_site/docs/drafts/2026-10-17-成本中心与销售事实-DDL草案.sql

-- ============================================================================
-- 通用成本中心 + 标准商品 + 销售事实（建表草案）
-- ----------------------------------------------------------------------------
-- 状态：草案（DRAFT）。**未接入** apps/backend/src/db/migrations。
--       接入时应拆成 `101_product_catalog.sql`、`102_cost_center.sql`、`103_sales_daily_facts.sql`，
--       并先跑 `npm run check:sql`（SQL 防退化护栏）。
-- 基线：main @ ccd5ed2a；数据依据：本地只读克隆（生产快照，orders 316,597，数据截至 2026-10-14）。
-- 金额单位：分（BIGINT）。本文件所有 *_fen 列均为分。
-- 设计依据：docs/成本中心与三块履约模型.md（三块载体、成本版本与快照）、docs/财务系统集成方案.md。
--
-- 目标（业务原话）：以后改成本只在一个地方。
--   -> 所有成本金额只写 cost_versions；业务表只保存 cost_snapshot_id 与派生金额，永不回写历史。
-- ============================================================================


-- ============================================================================
-- §1 标准商品主数据
-- ----------------------------------------------------------------------------
-- 为什么必须先做：同一个商品名对应多个 sku_code（实测「苏尔南钻石100颗」47 个码、
-- 「指挥官密钥1个」42 个码），直接按 sku_code 或 sku_name 统计都会出错。
-- ============================================================================

CREATE TABLE IF NOT EXISTS product_catalog (
  id                BIGSERIAL PRIMARY KEY,
  canonical_sku     TEXT NOT NULL,
  canonical_name    TEXT NOT NULL,
  category_id       BIGINT,
  unit_name         TEXT NOT NULL DEFAULT '件',
  status            TEXT NOT NULL DEFAULT 'active',
  attributes_json   JSONB NOT NULL DEFAULT '{}'::jsonb,
  created_at        TIMESTAMPTZ NOT NULL,
  updated_at        TIMESTAMPTZ NOT NULL
);

CREATE UNIQUE INDEX IF NOT EXISTS uq_product_catalog_canonical_sku ON product_catalog (canonical_sku);
CREATE INDEX IF NOT EXISTS idx_product_catalog_category ON product_catalog (category_id);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_product_catalog_status') THEN
    ALTER TABLE product_catalog
      ADD CONSTRAINT chk_product_catalog_status CHECK (status IN ('active', 'archived'));
  END IF;
END $$;

COMMENT ON TABLE  product_catalog IS '标准商品/皮肤主数据：报表统计口径的唯一入口';
COMMENT ON COLUMN product_catalog.canonical_sku IS '标准编码，报表维度用它，不用原始 sku_code';
COMMENT ON COLUMN product_catalog.unit_name IS '计量单位：件/个/颗，配合 normalized_quantity 使用';

-- 渠道映射：来源 + 店铺 + 平台SKU -> 标准商品
CREATE TABLE IF NOT EXISTS channel_product_mappings (
  id                  BIGSERIAL PRIMARY KEY,
  provider            TEXT NOT NULL,
  shop_id             TEXT NOT NULL DEFAULT '',
  platform_sku_code   TEXT NOT NULL,
  platform_sku_name   TEXT NOT NULL DEFAULT '',
  canonical_product_id BIGINT NOT NULL REFERENCES product_catalog(id) ON DELETE RESTRICT,
  quantity_multiplier INTEGER NOT NULL DEFAULT 1,
  confidence          TEXT NOT NULL DEFAULT 'manual',
  note                TEXT NOT NULL DEFAULT '',
  created_at          TIMESTAMPTZ NOT NULL,
  updated_at          TIMESTAMPTZ NOT NULL
);

-- 同一来源+店铺+SKU 只能映射到一个标准商品；shop_id 为空表示该来源的全局映射
CREATE UNIQUE INDEX IF NOT EXISTS uq_channel_product_mappings_key
  ON channel_product_mappings (provider, shop_id, platform_sku_code);
CREATE INDEX IF NOT EXISTS idx_channel_product_mappings_product
  ON channel_product_mappings (canonical_product_id);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_channel_product_mappings_confidence') THEN
    ALTER TABLE channel_product_mappings
      ADD CONSTRAINT chk_channel_product_mappings_confidence
      CHECK (confidence IN ('exact', 'rule', 'manual'));
  END IF;
END $$;

COMMENT ON TABLE  channel_product_mappings IS '来源+店铺+平台SKU -> 标准商品映射（报表口径归一化）';
COMMENT ON COLUMN channel_product_mappings.quantity_multiplier IS 'SKU 名称内含数量时的换算系数，例如「5个」=5';


-- ============================================================================
-- §2 成本中心
-- ============================================================================

-- 成本项：定义成本类型与计价方式，不存金额
CREATE TABLE IF NOT EXISTS cost_items (
  id             BIGSERIAL PRIMARY KEY,
  code           TEXT NOT NULL,
  name           TEXT NOT NULL,
  cost_type      TEXT NOT NULL,
  carrier_type   TEXT NOT NULL,
  pricing_mode   TEXT NOT NULL,
  currency       TEXT NOT NULL DEFAULT 'CNY',
  status         TEXT NOT NULL DEFAULT 'active',
  note           TEXT NOT NULL DEFAULT '',
  created_at     TIMESTAMPTZ NOT NULL,
  updated_at     TIMESTAMPTZ NOT NULL
);

CREATE UNIQUE INDEX IF NOT EXISTS uq_cost_items_code ON cost_items (code);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_items_cost_type') THEN
    ALTER TABLE cost_items
      ADD CONSTRAINT chk_cost_items_cost_type
      CHECK (cost_type IN ('auto_purchase', 'work_order_reward', 'manual_service', 'platform_fee', 'payment_fee', 'other'));
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_items_carrier_type') THEN
    ALTER TABLE cost_items
      ADD CONSTRAINT chk_cost_items_carrier_type
      CHECK (carrier_type IN ('affiliate_dash', 'work_order', 'legacy', 'manual', 'shared'));
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_items_pricing_mode') THEN
    ALTER TABLE cost_items
      ADD CONSTRAINT chk_cost_items_pricing_mode
      CHECK (pricing_mode IN ('per_item', 'per_order', 'per_hour', 'percent_of_revenue', 'fixed_daily'));
  END IF;
END $$;

COMMENT ON TABLE  cost_items IS '成本项定义：类型 + 载体 + 计价方式；金额一律放 cost_versions';
COMMENT ON COLUMN cost_items.carrier_type IS '适用执行载体；shared 表示与载体无关的通用成本（如支付通道费）';

-- 成本版本：**唯一改价入口**，按生效时间新增版本，永不覆盖历史
CREATE TABLE IF NOT EXISTS cost_versions (
  id              BIGSERIAL PRIMARY KEY,
  cost_item_id    BIGINT NOT NULL REFERENCES cost_items(id) ON DELETE RESTRICT,
  provider        TEXT NOT NULL DEFAULT '',
  shop_id         TEXT NOT NULL DEFAULT '',
  canonical_product_id BIGINT REFERENCES product_catalog(id) ON DELETE RESTRICT,
  category_id     BIGINT,
  amount_fen      BIGINT NOT NULL,
  effective_from  TIMESTAMPTZ NOT NULL,
  effective_to    TIMESTAMPTZ,
  approval_status TEXT NOT NULL DEFAULT 'approved',
  approved_by     TEXT NOT NULL DEFAULT '',
  reason          TEXT NOT NULL DEFAULT '',
  created_at      TIMESTAMPTZ NOT NULL,
  updated_at      TIMESTAMPTZ NOT NULL
);

-- 同一成本项 + 同一适用范围 + 同一生效时间只能有一个版本
CREATE UNIQUE INDEX IF NOT EXISTS uq_cost_versions_scope
  ON cost_versions (cost_item_id, provider, shop_id, coalesce(canonical_product_id, 0), effective_from);
CREATE INDEX IF NOT EXISTS idx_cost_versions_lookup
  ON cost_versions (cost_item_id, effective_from DESC);
CREATE INDEX IF NOT EXISTS idx_cost_versions_product
  ON cost_versions (canonical_product_id, effective_from DESC);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_versions_amount') THEN
    ALTER TABLE cost_versions ADD CONSTRAINT chk_cost_versions_amount CHECK (amount_fen >= 0);
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_versions_period') THEN
    ALTER TABLE cost_versions
      ADD CONSTRAINT chk_cost_versions_period
      CHECK (effective_to IS NULL OR effective_to > effective_from);
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_versions_approval') THEN
    ALTER TABLE cost_versions
      ADD CONSTRAINT chk_cost_versions_approval
      CHECK (approval_status IN ('draft', 'pending', 'approved', 'rejected'));
  END IF;
END $$;

COMMENT ON TABLE  cost_versions IS '成本版本：改价只在这里新增版本；历史成本靠 cost_snapshots 固化，不回写';
COMMENT ON COLUMN cost_versions.amount_fen IS '金额（分）。pricing_mode=percent_of_revenue 时表示万分比';
COMMENT ON COLUMN cost_versions.shop_id IS '空串=不限店铺；解析优先级 店铺+SKU > SKU > 分类 > 来源 > 全局';

-- 成本快照：每笔订单项/工单/人工单实际用了哪个版本、多少钱
CREATE TABLE IF NOT EXISTS cost_snapshots (
  id                   BIGSERIAL PRIMARY KEY,
  subject_type         TEXT NOT NULL,
  subject_id           BIGINT NOT NULL,
  order_id             BIGINT,
  order_item_id        BIGINT,
  work_order_id        BIGINT,
  carrier_type         TEXT NOT NULL,
  cost_item_id         BIGINT REFERENCES cost_items(id) ON DELETE RESTRICT,
  cost_version_id      BIGINT REFERENCES cost_versions(id) ON DELETE RESTRICT,
  canonical_product_id BIGINT REFERENCES product_catalog(id) ON DELETE RESTRICT,
  quantity             NUMERIC(14, 3) NOT NULL DEFAULT 1,
  unit_amount_fen      BIGINT NOT NULL DEFAULT 0,
  total_amount_fen     BIGINT NOT NULL DEFAULT 0,
  source               TEXT NOT NULL DEFAULT 'resolved',
  resolved_at          TIMESTAMPTZ NOT NULL,
  created_at           TIMESTAMPTZ NOT NULL
);

CREATE INDEX IF NOT EXISTS idx_cost_snapshots_subject ON cost_snapshots (subject_type, subject_id);
CREATE INDEX IF NOT EXISTS idx_cost_snapshots_item ON cost_snapshots (order_item_id);
CREATE INDEX IF NOT EXISTS idx_cost_snapshots_work_order ON cost_snapshots (work_order_id);
-- 幂等：同一主体 + 同一成本项只允许一条快照
CREATE UNIQUE INDEX IF NOT EXISTS uq_cost_snapshots_subject_item
  ON cost_snapshots (subject_type, subject_id, cost_item_id);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_snapshots_subject_type') THEN
    ALTER TABLE cost_snapshots
      ADD CONSTRAINT chk_cost_snapshots_subject_type
      CHECK (subject_type IN ('order_item', 'work_order', 'manual_case'));
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_snapshots_source') THEN
    ALTER TABLE cost_snapshots
      ADD CONSTRAINT chk_cost_snapshots_source
      CHECK (source IN ('resolved', 'legacy_rule', 'manual_input', 'missing'));
  END IF;
END $$;

COMMENT ON TABLE  cost_snapshots IS '成本快照：下单/建工单/人工完成时固化，后续改价不影响历史';
COMMENT ON COLUMN cost_snapshots.source IS 'resolved=命中成本中心；legacy_rule=回退旧 work_product_rules 金额；missing=未匹配到（禁止默认 0）';

-- 成本异常队列：匹配不到成本不能默认 0，必须进队列
CREATE TABLE IF NOT EXISTS cost_exceptions (
  id            BIGSERIAL PRIMARY KEY,
  subject_type  TEXT NOT NULL,
  subject_id    BIGINT NOT NULL,
  order_item_id BIGINT,
  work_order_id BIGINT,
  carrier_type  TEXT NOT NULL,
  reason        TEXT NOT NULL,
  status        TEXT NOT NULL DEFAULT 'open',
  detail_json   JSONB NOT NULL DEFAULT '{}'::jsonb,
  created_at    TIMESTAMPTZ NOT NULL,
  resolved_at   TIMESTAMPTZ,
  resolved_by   TEXT NOT NULL DEFAULT ''
);

CREATE UNIQUE INDEX IF NOT EXISTS uq_cost_exceptions_subject
  ON cost_exceptions (subject_type, subject_id, reason);
CREATE INDEX IF NOT EXISTS idx_cost_exceptions_open
  ON cost_exceptions (status, created_at DESC);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_cost_exceptions_status') THEN
    ALTER TABLE cost_exceptions
      ADD CONSTRAINT chk_cost_exceptions_status CHECK (status IN ('open', 'resolved', 'ignored'));
  END IF;
END $$;

COMMENT ON TABLE cost_exceptions IS '成本缺失/冲突异常队列：报表必须把 open 数量暴露出来，禁止静默按 0 计';


-- ============================================================================
-- §3 订单项口径补齐（金额与数量）
-- ----------------------------------------------------------------------------
-- 现状实测：order_items 只有 sku_code/sku_name/quantity/spec_json/snapshot，**没有任何金额列**；
--           且 quantity 不可信（316,585 项里 316,578 项 = 1，名称带「N个」的有 104,710 项）。
-- 现状利好：目前每笔已支付订单恰好 1 个订单项（316,585 单 = 316,585 项），
--           所以 orders.total_amount 暂时可当订单项收入；但 schema 允许多项，属**潜在**缺口。
--
-- 【口径已确认 2026-10-17】收入 = 用户付款金额，取 orders.total_amount：
--   · 91：total_amount 即用户付款（与快手发码配合）。数据核验：91 已支付 312,569 笔中
--         235,271 笔含快手 kuaishouSendCode.paymentFen，其中 235,268 笔与 total_amount **完全一致**
--         （100.00%），仅 3 笔差 ¥1.80~2.00（2026-09-05 / 09-18 / 10-04，可单独抽查）。
--   · PDD：order_amount；抖音：pay_amount。三者同为“用户实付”，故统一 revenue_basis = 'user_payment'。
--   · 打手报酬 = **支出/成本**（最终由打手提现、我方付款），因此按**总额法**：
--     收入记用户实付全额，打手报酬作为履约成本，不做代收代付净额。
--   · 退款/仲裁**暂未接入**：refunded_amount_fen / refunded_at 为**预留字段**，本轮不写逻辑。
-- ============================================================================

ALTER TABLE order_items
  ADD COLUMN IF NOT EXISTS canonical_product_id BIGINT REFERENCES product_catalog(id) ON DELETE RESTRICT,
  ADD COLUMN IF NOT EXISTS normalized_quantity INTEGER,
  ADD COLUMN IF NOT EXISTS revenue_amount_fen BIGINT,
  ADD COLUMN IF NOT EXISTS revenue_basis TEXT NOT NULL DEFAULT '',
  ADD COLUMN IF NOT EXISTS refunded_amount_fen BIGINT NOT NULL DEFAULT 0,
  ADD COLUMN IF NOT EXISTS refunded_at TIMESTAMPTZ;

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_order_items_revenue_basis') THEN
    ALTER TABLE order_items
      ADD CONSTRAINT chk_order_items_revenue_basis
      CHECK (revenue_basis IN ('', 'user_payment', 'manual_adjustment'));
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_order_items_revenue_amount') THEN
    ALTER TABLE order_items ADD CONSTRAINT chk_order_items_revenue_amount CHECK (revenue_amount_fen IS NULL OR revenue_amount_fen >= 0);
  END IF;
END $$;

CREATE INDEX IF NOT EXISTS idx_order_items_canonical_product ON order_items (canonical_product_id);

COMMENT ON COLUMN order_items.normalized_quantity IS '归一化件数：从 SKU 名称解析并固化，禁止直接用 quantity 做销量';
COMMENT ON COLUMN order_items.revenue_amount_fen IS '收入（分）= 用户实付，取 orders.total_amount；revenue_basis 通常为 user_payment';
COMMENT ON COLUMN order_items.refunded_at IS '【预留】退款时间：退款/仲裁暂未接入，本轮不写逻辑；接入后按日净销售额 = 销售额 - 退款额';

-- 过渡：让工单规则逐步改用成本中心（有 cost_item_id 走成本中心，否则回退旧金额字段）
ALTER TABLE work_product_rules
  ADD COLUMN IF NOT EXISTS cost_item_id BIGINT REFERENCES cost_items(id) ON DELETE RESTRICT,
  ADD COLUMN IF NOT EXISTS legacy_cost_source TEXT NOT NULL DEFAULT 'rule_amount';

CREATE INDEX IF NOT EXISTS idx_work_product_rules_cost_item ON work_product_rules (cost_item_id);

COMMENT ON COLUMN work_product_rules.cost_item_id IS '迁移用过渡列：非空则金额取成本中心，空则回退 reward_amount/unit_price_fen';
COMMENT ON COLUMN work_product_rules.legacy_cost_source IS '回退来源标记：rule_amount=旧规则金额，便于统计未迁移规则数';
-- 口径已确认（2026-10-17）：打手报酬是**支出**（工单结算 -> 可提现 -> 提现打款），
-- 按总额法计入履约成本，与用户实付收入分开记，不做代收代付净额。


-- ============================================================================
-- §4 销售事实表（店铺 × 日期 × 标准商品）
-- ============================================================================

CREATE TABLE IF NOT EXISTS sales_daily_facts (
  id                   BIGSERIAL PRIMARY KEY,
  stat_date            DATE NOT NULL,
  provider             TEXT NOT NULL,
  shop_id              TEXT NOT NULL DEFAULT '',
  canonical_product_id BIGINT NOT NULL REFERENCES product_catalog(id) ON DELETE RESTRICT,
  carrier_type         TEXT NOT NULL,
  order_count          INTEGER NOT NULL DEFAULT 0,
  item_count           INTEGER NOT NULL DEFAULT 0,
  gross_revenue_fen    BIGINT NOT NULL DEFAULT 0,
  refund_amount_fen    BIGINT NOT NULL DEFAULT 0,
  net_revenue_fen      BIGINT NOT NULL DEFAULT 0,
  cost_amount_fen      BIGINT NOT NULL DEFAULT 0,
  cost_missing_count   INTEGER NOT NULL DEFAULT 0,
  gross_profit_fen     BIGINT NOT NULL DEFAULT 0,
  computed_at          TIMESTAMPTZ NOT NULL,
  created_at           TIMESTAMPTZ NOT NULL,
  updated_at           TIMESTAMPTZ NOT NULL
);

CREATE UNIQUE INDEX IF NOT EXISTS uq_sales_daily_facts_key
  ON sales_daily_facts (stat_date, provider, shop_id, canonical_product_id, carrier_type);
CREATE INDEX IF NOT EXISTS idx_sales_daily_facts_date ON sales_daily_facts (stat_date DESC);
CREATE INDEX IF NOT EXISTS idx_sales_daily_facts_shop ON sales_daily_facts (provider, shop_id, stat_date DESC);

DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_sales_daily_facts_carrier') THEN
    ALTER TABLE sales_daily_facts
      ADD CONSTRAINT chk_sales_daily_facts_carrier
      CHECK (carrier_type IN ('affiliate_dash', 'work_order', 'legacy', 'manual'));
  END IF;
  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'chk_sales_daily_facts_profit') THEN
    ALTER TABLE sales_daily_facts
      ADD CONSTRAINT chk_sales_daily_facts_profit
      CHECK (gross_profit_fen = net_revenue_fen - cost_amount_fen);
  END IF;
END $$;

COMMENT ON TABLE  sales_daily_facts IS '店铺×日期(Asia/Shanghai)×标准商品×载体 的销售与成本事实；报表直接用这张表';
COMMENT ON COLUMN sales_daily_facts.stat_date IS '销售日按 Asia/Shanghai 归属，取 paid_at；退款按 refunded_at 归期';
COMMENT ON COLUMN sales_daily_facts.cost_missing_count IS '成本缺失件数：>0 时该行毛利不可信，报表必须标注';


-- ============================================================================
-- §5 校验与重算（跑完后必须对平，差异不为 0 说明实现有问题）
-- ============================================================================

-- Q1 成本解析覆盖率：open 异常占比应低于约定阈值，且不得为 0 成本静默通过
-- SELECT carrier_type, count(*) FILTER (WHERE source = 'missing') AS missing,
--        count(*) AS total,
--        round(100.0 * count(*) FILTER (WHERE source = 'missing') / count(*), 2) AS missing_pct
-- FROM cost_snapshots GROUP BY 1;

-- Q2 毛利守恒：销售事实的净收入必须等于订单项收入汇总（按同一维度）
-- SELECT f.stat_date, f.provider, f.shop_id,
--        f.net_revenue_fen AS fact_revenue,
--        coalesce(sum(oi.revenue_amount_fen - oi.refunded_amount_fen), 0) AS item_revenue
-- FROM sales_daily_facts f
-- LEFT JOIN order_items oi ON oi.canonical_product_id = f.canonical_product_id
-- LEFT JOIN orders o ON o.id = oi.order_id AND o.provider = f.provider AND o.shop_id = f.shop_id
-- GROUP BY 1, 2, 3, f.net_revenue_fen
-- HAVING f.net_revenue_fen <> coalesce(sum(oi.revenue_amount_fen - oi.refunded_amount_fen), 0)
-- LIMIT 100;

-- Q3 历史成本不回写校验：改 cost_versions 后，已有 cost_snapshots 金额不得变化
-- SELECT count(*) FROM cost_snapshots WHERE resolved_at < now() - interval '1 day' AND created_at <> resolved_at;


-- ============================================================================
-- §6 落地顺序（与 docs/成本中心与三块履约模型.md §九 一致）
--   1) §1 商品主数据 + 渠道映射  -> 解决「同一商品 47 个 SKU 码」与销量口径
--   2) §3 订单项口径（数量/收入）-> 解决 7.3 倍数量低估与收入口径不统一
--   3) §2 成本中心影子期        -> 自动发货接上游固定成本；工单接现有规则金额；人工接按单成本
--   4) §4 销售事实表            -> 店铺/日期/皮肤 的销量、收入、成本、毛利
--   5) 之后才是影子总账（docs/财务系统集成方案.md）
--
-- 【口径已确认 2026-10-17】
--   a) 收入 = 用户付款金额（orders.total_amount），计收入；已用数据核验与快手 paymentFen 100% 对齐。
--   b) 打手报酬 = 支出/成本（最终提现打款），按总额法。
--   c) 人工块：第一优先级是**人工支出可追溯**（付款项目/金额/订单号/付款人/凭证），
--      见 `2026-10-17-人工支出登记-DDL草案.sql`；按单还是按小时的取值口径仍待定，先按单登记。
--   d) 退款/仲裁：**暂未接入，先预留**（字段 + reversal_of_id + 事件类型，不实现逻辑）。
--
-- 【仍待确认】
--   1) 收入确认时点（付款 / 发货 / 验收 / 售后期结束）——影响利润表与预收账款；
--   2) 自动发货 cost_amount 是否稳定、是否含平台积分/汇率；
--   3) 平台服务费/支付通道费由谁承担、结算周期与账单口径；
--   4) 寄卖货款的采购成本确认时点。
-- ============================================================================