Inserting ClickHouse Data

This section describes the sample code for inserting ClickHouse data.

The following code snippet is provided in the createTable method of the Demo class in the com.huawei.clickhouse.examples package.

The table created in Creating a ClickHouse Table has three fields of the String, UInt8, and Date types.

String insertSql = "insert into " + databaseName + "." + tableName + " values (?,?,?)";
PreparedStatement preparedStatement = connection.prepareStatement(insertSql);
long allBatchBegin = System.currentTimeMillis();
for (int j = 0; j < batchNum; j++) {
    for (int i = 0; i < batchRows; i++) { 
       preparedStatement.setString(1, "huawei_" + (i + j * 10));
       preparedStatement.setInt(2, ((int) (Math.random() * 100)));
       preparedStatement.setDate(3, generateRandomDate("2018-01-01", "2021-12-31")); 
       preparedStatement.addBatch();
    }
   long begin = System.currentTimeMillis();
   preparedStatement.executeBatch();    
   long end = System.currentTimeMillis();
   log.info("Inert batch time is {} ms", end - begin);
}
long allBatchEnd = System.currentTimeMillis();
log.info("Inert all batch time is {} ms", allBatchEnd - allBatchBegin);