@arm.tech/clckh
v0.0.5-rc
Published
ClickHouse is an open source column-oriented database management system capable of real time generation of analytical data reports using SQL queries.
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@arm.tech/clckh
NodeJS client for ClickHouse. Send query over HTTP interface.
Install:
npm i @arm.tech/clckh
Example:
const ClickHouse = require('@arm.tech/clckh');
const clckh = new ClickHouse();
or with all options:
const clckh = new ClickHouse({
url: 'http://localhost',
port: 8123,
debug: false,
basicAuth: null,
isUseGzip: false,
format: "json", // "json" || "csv" || "tsv"
config: {
session_timeout : 60,
output_format_json_quote_64bit_integers : 0,
enable_http_compression : 0
},
// This object merge with request params (see request lib docs)
reqParams: {
...
}
});
or change
basicAuth: null
to
basicAuth: {
username: 'default',
password: '',
},
Exec query:
const queries = [
'DROP TABLE IF EXISTS session_temp',
`CREATE TABLE session_temp (
date Date,
time DateTime,
mark String,
ips Array(UInt32),
queries Nested (
act String,
id UInt32
)
)
ENGINE=MergeTree(date, (mark, time), 8192)`,
'OPTIMIZE TABLE ukit.loadstat PARTITION 201807 FINAL'
];
for(const query of queries) {
const r = await clckh.query(query).toPromise();
console.log(query, r);
}
Exec by callback way:
clckh.query(query).exec(function (err, rows) {
...
});
Stream:
clckh.query(`SELECT number FROM system.numbers LIMIT 10`).stream()
.on('data', function() {
const stream = this;
stream.pause();
setTimeout(() => {
stream.resume();
}, 1000);
})
.on('error', err => {
...
})
.on('end', () => {
...
});
or async stream:
// async iteration
for await (const row of clckh.query(sql).stream()) {
console.log(row);
}
As promise:
const rows = await clckh.query(query).toPromise();
// use query with external data
const rows = await clckh.query('SELECT * AS count FROM temp_table', {
external: [
{
name: 'temp_table',
data: e._.range(0, rowCount).map(i => `str${i}`)
},
]
}).toPromise();
Set session:
clckh.sessionId = '...';
const r = await clckh.query(
`CREATE TEMPORARY TABLE test_table
(_id String, str String)
ENGINE=Memory`
).toPromise();
Insert stream:
const ws = clckh.insert('INSERT INTO session_temp').stream();
for(let i = 0; i <= 1000; i++) {
await ws.writeRow(
[
e._.range(0, 50).map(
j => `${i}:${i * 2}:${j}`
).join('-')
]
);
}
//wait stream finish
const result = await ws.exec();
Pipe readable stream to writable stream (across transform):
const rs = clckh.query(query).stream();
const tf = new stream.Transform({
objectMode : true,
transform : function (chunk, enc, cb) {
cb(null, JSON.stringify(chunk) + '\n');
}
});
clckh.sessionId = Date.now();
const ws = clckh.insert('INSERT INTO session_temp2').stream();
const result = await rs.pipe(tf).pipe(ws).exec();