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This article mainly introduces how to use Hbase, which has certain reference value. Interested friends can refer to it. I hope you will gain a lot after reading this article. Let Xiaobian take you to understand it together.

Compare with MySQL:

1 To create a table, you only need to specify the famly column family. You do not need to specify specific columns and types.

@PostConstruct

public boolean createTable() {

log.info("create table start");

TableName tableName = TableName.valueOf(this.getTableName());

try {

Admin admin = connection.getAdmin();

if (! admin.tableExists(tableName)) {

log.info(tableName.toString() + "is not exist,create it");

HTableDescriptor tdesc = new HTableDescriptor(tableName);

HColumnDescriptor colDesc = new HColumnDescriptor(FAMILY);

tdesc.addFamily(colDesc);

admin.createTable(tdesc);

admin.close();

}

log.info("create table end");

return true;

} catch ( IOException e) {

log.error("create table error {} {}", tableName, e.getLocalizedMessage());

return false;

}

}

2 Storage data format HBASE value All byte[] byte data format storage

Advantages: 1 No need to process data types in advance unified use Bytes.toByte() so storage speed is higher

2 Compared with the original data type, serialized byte[] form storage can save bytes

3 can be based on rowKey range search, this need to rowKey design properly.

@Override

public List getByRange(String start, String end) {

try {

Table table = connection.getTable(TableName.valueOf(getTableName()));

Scan scan = new Scan();

scan.withStartRow(start.getBytes(), true)

.withStopRow(end.getBytes(), true);

ResultScanner scanner = table.getScanner(scan);

List list = new ArrayList();

for (Result result : scanner) {

list.add(getObj(result));

}

return list;

} catch (Exception e) {

log.error("HBase failed to get data in bulk", e);

}

return Collections.emptyList();}

Thank you for reading this article carefully. I hope that the article "How to Use Hbase" shared by Xiaobian will be helpful to everyone. At the same time, I hope that everyone will support you a lot and pay attention to the industry information channel. More relevant knowledge is waiting for you to learn!

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