Enabling a Table using HBase Shell
Syntax
enable ‘table_name’
E.g
hbase> enable 'emp' 0 row(s) in 0.5810 seconds
Verification
After enabling the table, scan it. If you can see the schema, your table is successfully enabled.
hbase> scan 'emp' ROW COLUMN + CELL 1 column = personal data:city, timestamp = 1417516501, value = bhimavaram 1 column = personal data:name, timestamp = 1417525058, value = ashok 1 column = professional data:designation, timestamp = 1417532601, value = software engineer 1 column = professional data:salary, timestamp = 1417524244109, value = 30000 2 column = personal data:city, timestamp = 1417524574905, value = chennai 2 column = personal data:name, timestamp = 1417524556125, value = vinod 2 column = professional data:designation, timestamp = 14175292204, value = cloud consultant 2 column = professional data:salary, timestamp = 1417524604221, value = 70000 2 row(s) in 0.0400 seconds
is_enabled
This command is used to find whether a table is enabled.
Syntax
hbase> is_enabled 'table name'
The following code verifies whether the table named emp is enabled. If it is enabled, it will return true and if not, it will return false.
hbase> is_enabled 'emp' true 0 row(s) in 0.0520 seconds
Enable a Table Using Java API
To verify whether a table is enabled, isTableEnabled() method is used; and to enable a table, enableTable() method is used. These methods belong to HBaseAdmin class.
package com.ashok.hbase; import java.io.IOException; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.HBaseConfiguration; import org.apache.hadoop.hbase.MasterNotRunningException; import org.apache.hadoop.hbase.client.HBaseAdmin; /** * * @author ashok.mariyala * */ public class EnableTable{ public static void main(String args[]) throws MasterNotRunningException, IOException{ // Instantiating configuration class Configuration conf = HBaseConfiguration.create(); // Instantiating HBaseAdmin class HBaseAdmin admin = new HBaseAdmin(conf); // Verifying weather the table is disabled Boolean bool = admin.isTableEnabled("emp"); System.out.println(bool); // Disabling the table using HBaseAdmin object if(!bool){ admin.enableTable("emp"); System.out.println("Table Enabled"); } } }
Enable a Table