-- 表：wms_allocation
-- 用途：库存分配。出库行预占到具体库位批次的记录，也是库存锁定明细。
-- 约定：InnoDB / utf8mb4 / 无外键，表间按业务编码关联。详见 docs/database/00-conventions.md
-- 说明：reserved 时 available 转为 reserved。released 时转回。picked 时 reserved 转为 picked。不另建预占表。

CREATE TABLE `wms_allocation` (
  `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '内部主键',
  `tenant_code` VARCHAR(32) NOT NULL COMMENT '租户编码',
  `allocation_no` VARCHAR(64) NOT NULL COMMENT '分配单号，租户内唯一',
  `outbound_no` VARCHAR(64) NOT NULL COMMENT '出库单号',
  `outbound_line_no` INT UNSIGNED NOT NULL COMMENT '出库行号',
  `warehouse_code` VARCHAR(32) NOT NULL COMMENT '仓库编码',
  `customer_code` VARCHAR(32) NOT NULL COMMENT '货主编码',
  `location_code` VARCHAR(64) NOT NULL COMMENT '库位编码',
  `sku_code` VARCHAR(64) NOT NULL COMMENT 'SKU 编码',
  `batch_no` VARCHAR(64) NOT NULL DEFAULT '' COMMENT '批次号，可空',
  `qty` DECIMAL(16,4) NOT NULL DEFAULT 0.0000 COMMENT '分配数量',
  `status` VARCHAR(32) NOT NULL DEFAULT 'reserved' COMMENT 'reserved 已预占，picked 已拣货，released 已释放',
  `created_at` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) COMMENT '创建时间',
  `updated_at` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3) COMMENT '更新时间',
  PRIMARY KEY (`id`),
  UNIQUE KEY `uk_tenant_allocation_no` (`tenant_code`, `allocation_no`),
  KEY `idx_tenant_outbound` (`tenant_code`, `outbound_no`),
  KEY `idx_tenant_sku_location` (`tenant_code`, `warehouse_code`, `sku_code`, `location_code`),
  CONSTRAINT `chk_allocation_qty` CHECK (`qty` > 0)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='库存分配';