homework-jianmu/docs/examples/node/websocketexample/stmt_example.js

76 lines
2.6 KiB
JavaScript

const taos = require("@tdengine/websocket");
let db = 'power';
let stable = 'meters';
let numOfSubTable = 10;
let numOfRow = 10;
let dsn = 'ws://localhost:6041'
function getRandomInt(min, max) {
min = Math.ceil(min);
max = Math.floor(max);
return Math.floor(Math.random() * (max - min + 1)) + min;
}
async function prepare() {
let conf = new taos.WSConfig(dsn);
conf.setUser('root')
conf.setPwd('taosdata')
conf.setDb(db)
let wsSql = await taos.sqlConnect(conf);
await wsSql.exec(`CREATE DATABASE IF NOT EXISTS ${db} KEEP 3650 DURATION 10 BUFFER 16 WAL_LEVEL 1;`);
await wsSql.exec(`CREATE STABLE IF NOT EXISTS ${db}.${stable} (ts timestamp, current float, voltage int, phase float) TAGS (location binary(64), groupId int);`);
return wsSql
}
async function test() {
let stmt = null;
let connector = null;
try {
connector = await prepare();
stmt = await connector.stmtInit();
await stmt.prepare(`INSERT INTO ? USING ${db}.${stable} (location, groupId) TAGS (?, ?) VALUES (?, ?, ?, ?)`);
for (let i = 0; i < numOfSubTable; i++) {
await stmt.setTableName(`d_bind_${i}`);
let tagParams = stmt.newStmtParam();
tagParams.setVarchar([`location_${i}`]);
tagParams.setInt([i]);
await stmt.setTags(tagParams);
let timestampParams = [];
let currentParams = [];
let voltageParams = [];
let phaseParams = [];
const currentMillis = new Date().getTime();
for (let j = 0; j < numOfRow; j++) {
timestampParams.push(currentMillis + j);
currentParams.push(Math.random() * 30);
voltageParams.push(getRandomInt(100, 300));
phaseParams.push(Math.random());
}
let bindParams = stmt.newStmtParam();
bindParams.setTimestamp(timestampParams);
bindParams.setFloat(currentParams);
bindParams.setInt(voltageParams);
bindParams.setFloat(phaseParams);
await stmt.bind(bindParams);
await stmt.batch();
await stmt.exec();
console.log("Successfully inserted " + stmt.getLastAffected() + " to power.meters.");
}
}
catch (err) {
console.error(`Failed to insert to table meters using stmt, ErrCode: ${err.code}, ErrMessage: ${err.message}`);
throw err;
}
finally {
if (stmt) {
await stmt.close();
}
if (connector) {
await connector.close();
}
taos.destroy();
}
}
test()