/clickhouse-jdbc

JDBC driver for ClickHouse

Primary LanguageJavaApache License 2.0Apache-2.0

ClickHouse JDBC driver

clickhouse-jdbc Build Status(https://github.com/ClickHouse/clickhouse-jdbc/workflows/Build/badge.svg) Coverage

This is a basic and restricted implementation of jdbc driver for ClickHouse. It has support of a minimal subset of features to be usable.

Usage

<dependency>
    <groupId>ru.yandex.clickhouse</groupId>
    <artifactId>clickhouse-jdbc</artifactId>
    <version>0.3.2</version>
</dependency>

URL syntax: jdbc:clickhouse://<host>:<port>[/<database>], e.g. jdbc:clickhouse://localhost:8123/test

JDBC Driver Class: ru.yandex.clickhouse.ClickHouseDriver

For example:

String url = "jdbc:clickhouse://localhost:8123/test";
ClickHouseProperties properties = new ClickHouseProperties();
// set connection options - see more defined in ClickHouseConnectionSettings
properties.setClientName("Agent #1");
...
// set default request options - more in ClickHouseQueryParam
properties.setSessionId("default-session-id");
...

ClickHouseDataSource dataSource = new ClickHouseDataSource(url, properties)
String sql = "select * from mytable";
Map<ClickHouseQueryParam, String> additionalDBParams = new HashMap<>();
// set request options, which will override the default ones in ClickHouseProperties
additionalDBParams.put(ClickHouseQueryParam.SESSION_ID, "new-session-id");
...
try (ClickHouseConnection conn = dataSource.getConnection();
    ClickHouseStatement stmt = conn.createStatement();
    ResultSet rs = stmt.executeQuery(sql, additionalDBParams)) {
    ...
}

Additionally, if you have a few instances, you can use BalancedClickhouseDataSource.

Extended API

In order to provide non-JDBC complaint data manipulation functionality, proprietary API exists. Entry point for API is ClickHouseStatement#write() method.

Importing file into table

import ru.yandex.clickhouse.ClickHouseStatement;
ClickHouseStatement sth = connection.createStatement();
sth
    .write() // Write API entrypoint
    .table("default.my_table") // where to write data
    .option("format_csv_delimiter", ";") // specific param
    .data(new File("/path/to/file.csv.gz"), ClickHouseFormat.CSV, ClickHouseCompression.gzip) // specify input     
    .send();

Configurable send

import ru.yandex.clickhouse.ClickHouseStatement;
ClickHouseStatement sth = connection.createStatement();
sth
    .write()
    .sql("INSERT INTO default.my_table (a,b,c)")
    .data(new MyCustomInputStream(), ClickHouseFormat.JSONEachRow)
    .dataCompression(ClickHouseCompression.brotli)    
    .addDbParam(ClickHouseQueryParam.MAX_PARALLEL_REPLICAS, 2)
    .send();

Send data in binary formatted with custom user callback

import ru.yandex.clickhouse.ClickHouseStatement;
ClickHouseStatement sth = connection.createStatement();
sth.write().send("INSERT INTO test.writer", new ClickHouseStreamCallback() {
    @Override
    public void writeTo(ClickHouseRowBinaryStream stream) throws IOException {
        for (int i = 0; i < 10; i++) {
            stream.writeInt32(i);
            stream.writeString("Name " + i);
        }
    }
},
ClickHouseFormat.RowBinary); // RowBinary or Native are supported

Supported Server Versions

All active releases are supported. You can still use the driver for older versions like 18.14 or 19.16 but please keep in mind that they're no longer supported.

Compiling with maven

The driver is built with maven. mvn package -DskipTests=true

To build a jar with dependencies use

mvn package assembly:single -DskipTests=true

Build requirements

In order to build the jdbc client one need to have jdk 1.8 or higher.