Hive - Drop Table


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This chapter describes how to drop a table in Hive. When you drop a table from Hive Metastore, it removes the table/column data and their metadata. It can be a normal table (stored in Metastore) or an external table (stored in local file system); Hive treats both in the same manner, irrespective of their types.

Drop Table Statement

The syntax is as follows:

DROP TABLE [IF EXISTS] table_name;

The following query drops a table named employee:

hive> DROP TABLE IF EXISTS employee;

On successful execution of the query, you get to see the following response:

OK
Time taken: 5.3 seconds
hive>

JDBC Program

The following JDBC program drops the employee table.

import java.sql.SQLException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.DriverManager;

public class HiveDropTable {

   private static String driverName = "org.apache.hadoop.hive.jdbc.HiveDriver";
   
   public static void main(String[] args) throws SQLException {
   
      // Register driver and create driver instance
      Class.forName(driverName);

      // get connection
      Connection con = DriverManager.getConnection("jdbc:hive://localhost:10000/userdb", "", "");

      // create statement
      Statement stmt = con.createStatement();

      // execute statement
      stmt.executeQuery("DROP TABLE IF EXISTS employee;");
      System.out.println("Drop table successful.");
      
      con.close();
   }
}

Save the program in a file named HiveDropTable.java. Use the following commands to compile and execute this program.

$ javac HiveDropTable.java
$ java HiveDropTable

Output:

Drop table successful

The following query is used to verify the list of tables:

hive> SHOW TABLES;
emp
ok
Time taken: 2.1 seconds
hive>


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