使用 Node.js 和 @clickhouse/client
main.ts。
Package.json (将其放在 ./ 目录下) ：
{
"name": "a simple clickhouse client example",
"version": "1.0.0",
"main": "main.js",
"license": "MIT",
"devDependencies": {
"typescript": "^5.3.2"
},
"dependencies": {
"@clickhouse/client": "^0.2.6"
}
}
Main.ts (放在 ./src 目录下) ：
import { ClickHouseClient, createClient } from '@clickhouse/client'; // or '@clickhouse/client-web'
interface ClickHouseResultSet<T> {
meta: Meta[];
data: T[];
rows: number;
statistics: Statistics;
}
interface Statistics {
elapsed: number;
rows_read: number;
bytes_read: number;
}
interface Meta {
name: string;
type: string;
}
interface Count {
c: number;
}
//请按需替换客户端连接参数，如 `host`、
//`username`、`passowrd`、`database` 等。
const initClickHouseClient = async (): Promise<ClickHouseClient> => {
const client = createClient({
host: 'https://FQDN.aws.clickhouse.cloud',
username: 'default',
password: 'password',
database: 'default',
application: `pingpong`,
});
console.log('ClickHouse ping');
if (!(await client.ping())) {
throw new Error('failed to ping clickhouse!');
}
console.log('ClickHouse pong!');
return client;
};
const main = async () => {
console.log('Initialising clickhouse client');
const client = await initClickHouseClient();
const row = await client.query({
query: `SELECT count() AS c FROM system.tables WHERE database='system'`,
});
const jsonRow: ClickHouseResultSet<Count> = await row.json();
console.log(`I have found ${jsonRow.data[0].c} system tables!`);
await client.close();
console.log(`👋`);
};
main();
./ 目录中运行 yarn：
$ yarn
yarn install v1.22.19
[1/4] 🔍 Resolving packages...
[2/4] 🚚 Fetching packages...
[3/4] 🔗 Linking dependencies...
[4/4] 🔨 Building fresh packages...
✨ Done in 0.14s.
./ 目录下运行 main.ts 中的代码：
$ npx ts-node src/main.ts
Initialising clickhouse client
ClickHouse ping
ClickHouse pong!
I have found 120 system tables!
👋