How can we check the total number of rows in a table in HBase?

You can use either the HBase shell or the HBase Java API to view the total number of rows in an HBase table.

You can view the total number of table data by following these steps using HBase shell.

1. – Interactive shell for HBase
2. take a quick look
3. the table that belongs to me
4. Results are gathered from the table named ‘my_table’.
5. .get the size()
6. the size of the results

With the HBase Java API, you can view the total number of table data by following these steps:

1. Create a Configuration object and a Connection object for HBase in Java code.
2. Create a Table object using the Connection object, specifying the table from which to retrieve the total number of data entries.
3. Instantiate a Scan object and configure its settings, such as scanning the entire table.
4. obtain the scanner
5. Iterate through the results line by line using the Scanner object and calculate the total number of data.
6. Close the Scanner object and Table object to release resources.

This is an example code using the HBase Java API to view the total number of data in a table.

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.client.*;

public class HBaseDataCount {
    public static void main(String[] args) {
        // 创建HBase的Configuration对象
        Configuration conf = HBaseConfiguration.create();

        try (Connection connection = ConnectionFactory.createConnection(conf)) {
            // 指定要查询数据总数的表名
            TableName tableName = TableName.valueOf("my_table");

            // 创建Table对象
            try (Table table = connection.getTable(tableName)) {
                // 创建一个Scan对象
                Scan scan = new Scan();

                // 获取结果Scanner对象
                try (ResultScanner scanner = table.getScanner(scan)) {
                    int count = 0;
                    // 遍历结果并计算数据总数
                    for (Result result : scanner) {
                        count++;
                    }
                    System.out.println("数据总数：" + count);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Please adjust the table name and other parameters according to your actual needs, and make sure to correctly configure the connection information for HBase in the code.