HBase - Exists


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Existence of Table using HBase Shell

You can verify the existence of a table using the exists command. The following example shows how to use this command.

hbase(main):024:0> exists 'emp'
Table emp does exist

0 row(s) in 0.0750 seconds

==================================================================

hbase(main):015:0> exists 'student'
Table student does not exist

0 row(s) in 0.0480 seconds

Verifying the Existence of Table Using Java API

You can verify the existence of a table in HBase using the tableExists() method of the HBaseAdmin class. Follow the steps given below to verify the existence of a table in HBase.

Step 1

Instantiate the HBaseAdimn class

// Instantiating configuration object
Configuration conf = HBaseConfiguration.create();

// Instantiating HBaseAdmin class
HBaseAdmin admin = new HBaseAdmin(conf); 

Step 2

Verify the existence of the table using the tableExists( ) method.

Given below is the java program to test the existence of a table in HBase using java API.

import java.io.IOException;

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

public class TableExists{

   public static void main(String args[])throws IOException{

      // Instantiating configuration class
      Configuration conf = HBaseConfiguration.create();

      // Instantiating HBaseAdmin class
      HBaseAdmin admin = new HBaseAdmin(conf);

      // Verifying the existance of the table
      boolean bool = admin.tableExists("emp");
      System.out.println( bool);
   }
} 

Compile and execute the above program as shown below.

$javac TableExists.java
$java TableExists 

The following should be the output:

true


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