Hive - Drop Database


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This chapter describes how to drop a database in Hive. The usage of SCHEMA and DATABASE are same.

Drop Database Statement

Drop Database is a statement that drops all the tables and deletes the database. Its syntax is as follows:

DROP DATABASE StatementDROP (DATABASE|SCHEMA) [IF EXISTS] database_name 
[RESTRICT|CASCADE];

The following queries are used to drop a database. Let us assume that the database name is userdb.

hive> DROP DATABASE IF EXISTS userdb;

The following query drops the database using CASCADE. It means dropping respective tables before dropping the database.

hive> DROP DATABASE IF EXISTS userdb CASCADE;

The following query drops the database using SCHEMA.

hive> DROP SCHEMA userdb;

This clause was added in Hive 0.6.

JDBC Program

The JDBC program to drop a database is given below.

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

public class HiveDropDb {
   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/default", "", "");
      Statement stmt = con.createStatement();
      stmt.executeQuery("DROP DATABASE userdb");
      
      System.out.println(“Drop userdb database successful.”);
      
      con.close();
   }
}

Save the program in a file named HiveDropDb.java. Given below are the commands to compile and execute this program.

$ javac HiveDropDb.java
$ java HiveDropDb

Output:

Drop userdb database successful.


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