try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
// The admin API lets us create, manage and delete tables
Admin admin = connection.getAdmin();
// [END bigtable_hw_connect]
// [START bigtable_hw_create_table]
// Create a table with a single column family
HTableDescriptor descriptor = new HTableDescriptor(TableName.valueOf(TABLE_NAME));
descriptor.addFamily(new HColumnDescriptor(COLUMN_FAMILY_NAME));
print("Create table " + descriptor.getNameAsString());
admin.createTable(descriptor);
// [END bigtable_hw_create_table]
// [START bigtable_hw_write_rows]
// Retrieve the table we just created so we can do some reads and writes
Table table = connection.getTable(TableName.valueOf(TABLE_NAME));
// Write some rows to the table
print("Write some greetings to the table");
for (int i = 0; i < GREETINGS.length; i++) {
// Each row has a unique row key.
//
// Note: This example uses sequential numeric IDs for simplicity, but
// this can result in poor performance in a production application.
// Since rows are stored in sorted order by key, sequential keys can
// result in poor distribution of operations across nodes.
//
// For more information about how to design a Bigtable schema for the
// best performance, see the documentation:
//
// https://cloud.google.com/bigtable/docs/schema-design
String rowKey = "greeting" + i;
// Put a single row into the table. We could also pass a list of Puts to write a batch.
Put put = new Put(Bytes.toBytes(rowKey));
put.addColumn(COLUMN_FAMILY_NAME, COLUMN_NAME, Bytes.toBytes(GREETINGS[i]));
table.put(put);
}
// [END bigtable_hw_write_rows]
// [START bigtable_hw_get_by_key]
// Get the first greeting by row key
String rowKey = "greeting0";
Result getResult = table.get(new Get(Bytes.toBytes(rowKey)));
String greeting = Bytes.toString(getResult.getValue(COLUMN_FAMILY_NAME, COLUMN_NAME));
System.out.println("Get a single greeting by row key");
System.out.printf("\t%s = %s\n", rowKey, greeting);
// [END bigtable_hw_get_by_key]
// [START bigtable_hw_scan_all]
// Now scan across all rows.
Scan scan = new Scan();
print("Scan for all greetings:");
ResultScanner scanner = table.getScanner(scan);
for (Result row : scanner) {
byte[] valueBytes = row.getValue(COLUMN_FAMILY_NAME, COLUMN_NAME);
System.out.println('\t' + Bytes.toString(valueBytes));
}
// [END bigtable_hw_scan_all]
// [START bigtable_hw_delete_table]
// Clean up by disabling and then deleting the table
print("Delete the table");
admin.disableTable(table.getName());
admin.deleteTable(table.getName());
// [END bigtable_hw_delete_table]
} catch (IOException e) {
System.err.println("Exception while running HelloWorld: " + e.getMessage());
e.printStackTrace();
System.exit(1);
}
System.exit(0);
}
1条答案
按热度按时间7y4bm7vi1#
hbase是键值存储。一般来说,这些不支持
join
操作本身。唯一的选择是读取两个hbase表(使用
scan
)然后点燃Sparkjoin
.看一看
java
举个例子。下面是和link中相同的代码,以防万一。