QueryIterator class

提取查询的所有页面并返回单个 FeedResponse。

示例

import { CosmosClient } from "@azure/cosmos";

const endpoint = "https://your-account.documents.azure.com";
const key = "<database account masterkey>";
const client = new CosmosClient({ endpoint, key });

const { database } = await client.databases.createIfNotExists({ id: "Test Database" });

const { container } = await database.containers.createIfNotExists({ id: "Test Container" });

const { resources } = await container.items
  .query("SELECT * from c WHERE c.isCapitol = true")
  .fetchAll();

function fetchAll(): Promise<FeedResponse<T>>

返回

从源中检索下一批。

这可能或可能不会根据设置和查询类型从后端提取更多页面。 聚合查询通常会在返回第一批响应之前提取所有后端页面。

示例

import { CosmosClient } from "@azure/cosmos";

const endpoint = "https://your-account.documents.azure.com";
const key = "<database account masterkey>";
const client = new CosmosClient({ endpoint, key });

const { database } = await client.databases.createIfNotExists({ id: "Test Database" });

const { container } = await database.containers.createIfNotExists({ id: "Test Container" });

const querySpec = {
  query: "SELECT c.status, COUNT(c.id) AS count FROM c GROUP BY c.status",
};
const queryOptions = {
  maxItemCount: 10, // maximum number of items to return per page
  enableCrossPartitionQuery: true,
};
const queryIterator = container.items.query(querySpec, queryOptions);
while (queryIterator.hasMoreResults()) {
  const { resources: result } = await queryIterator.fetchNext();
  // process results
}

function fetchNext(): Promise<FeedResponse<T>>

返回

获取一个异步迭代器，它将在完成之前生成结果。

注意：AsyncIterator 是一项非常新功能，可能需要使用 polyfils/etc，才能在代码中使用它们。

如果使用 TypeScript，只要面向 ES6 或更高版本且在 Node 6 或更高版本上运行，就可以使用以下填充。

if (!Symbol || !Symbol.asyncIterator) {
  (Symbol as any).asyncIterator = Symbol.for("Symbol.asyncIterator");
}

示例

循环访问所有数据库

import { CosmosClient } from "@azure/cosmos";

const endpoint = "https://your-account.documents.azure.com";
const key = "<database account masterkey>";
const client = new CosmosClient({ endpoint, key });

for await (const { resources: db } of client.databases.readAll().getAsyncIterator()) {
  console.log(`Got ${db} from AsyncIterator`);
}

function getAsyncIterator(): AsyncIterable<FeedResponse<T>>

返回

根据继续标记的值或 QueryIterator 中当前批剩余的元素，确定是否仍有剩余的资源要处理。

function hasMoreResults(): boolean

返回

如果查询Iterator 中还有其他要处理的元素，则为 true。

将 QueryIterator 重置为开头并清除其中的所有资源

示例

import { CosmosClient } from "@azure/cosmos";

const endpoint = "https://your-account.documents.azure.com";
const key = "<database account masterkey>";
const client = new CosmosClient({ endpoint, key });
const { database } = await client.databases.createIfNotExists({ id: "Test Database" });
const { container } = await database.containers.createIfNotExists({ id: "Test Container" });

const querySpec = {
  query: "SELECT c.status, COUNT(c.id) AS count FROM c GROUP BY c.status",
};
const queryIterator = container.items.query(querySpec);
while (queryIterator.hasMoreResults()) {
  const { resources: result } = await queryIterator.fetchNext();
  // process results
}
queryIterator.reset();

function reset()