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Multi-Point Region Splitting

Function Description

You can perform multi-point splitting by using org.apache.hadoop.hbase.client.HBaseAdmin.

The splitting operation takes effect on empty regions only.

In MRS 2.0.0 or later, the API is removed and does not support this function. You can pre-partition a table when creating the table or directly perform split operations in some regions.

In this example, the multi-point splitting is performed on an HBase table by using multiSplit. The table will be split into four regions: "A~D", "D~F", "F~H", and "H~Z".

Sample Code

The following code snippets are in the testMultiSplit method in the HBaseExample class of the com.huawei.bigdata.hbase.examples packet.

public void testMultiSplit() {
    LOG.info("Entering testMultiSplit.");

    Table table = null;
    Admin admin = null;
    try {
        admin = conn.getAdmin();

        // initilize a HTable object
        table = conn.getTable(tableName);
        Set<HRegionInfo> regionSet = new HashSet<HRegionInfo>();
        List<HRegionLocation> regionList = conn.getRegionLocator(tableName).getAllRegionLocations();
        for (HRegionLocation hrl : regionList) {
            regionSet.add(hrl.getRegionInfo());
        }
        byte[][] sk = new byte[4][];
        sk[0] = "A".getBytes();
        sk[1] = "D".getBytes();
        sk[2] = "F".getBytes();
        sk[3] = "H".getBytes();
        for (HRegionInfo regionInfo : regionSet) {
            ((HBaseAdmin) admin).multiSplit(regionInfo.getRegionName(), sk);
        }
        LOG.info("MultiSplit successfully.");
    } catch (Exception e) {
        LOG.error("MultiSplit failed ", e);
    } finally {
        if (table != null) {
            try {
                // Close table object
                table.close();
            } catch (IOException e) {
                LOG.error("Close table failed ", e);
            }
        }
        if (admin != null) {
            try {
                // Close the Admin object.
                admin.close();
            } catch (IOException e) {
                LOG.error("Close admin failed ", e);
            }
        }
    }
    LOG.info("Exiting testMultiSplit.");
}
Parent topic: Application Development