It is very easy to drop an existing HSQLDB table. However, you need to be very careful while deleting any existing table as any data lost will not be recovered after deleting a table.
Following is a generic SQL syntax to drop a HSQLDB table.
DROP TABLE table_name;
Let us consider an example to drop a table named employee from the HSQLDB server. Following is the query to drop a table named employee.
DROP TABLE employee;
After execution of the above query, you will receive the following output −
(0) rows effected
Following is the JDBC program used to drop the table employee from the HSQLDB server.
Save the following code into DropTable.java file.
import java.sql.Connection; import java.sql.DriverManager; import java.sql.Statement; public class DropTable { public static void main(String[] args) { Connection con = null; Statement stmt = null; int result = 0; try { Class.forName("org.hsqldb.jdbc.JDBCDriver"); con = DriverManager.getConnection("jdbc:hsqldb:hsql://localhost/testdb", "SA", ""); stmt = con.createStatement(); result = stmt.executeUpdate("DROP TABLE employee"); }catch (Exception e) { e.printStackTrace(System.out); } System.out.println("Table dropped successfully"); } }
You can start the database using the following command.
\>cd C:\hsqldb-2.3.4\hsqldb hsqldb>java -classpath lib/hsqldb.jar org.hsqldb.server.Server --database.0 file:hsqldb/demodb --dbname.0 testdb
Compile and execute the above program using the following command.
\>javac DropTable.java \>java DropTable
After execution of the above command, you will receive the following output −
Table dropped successfully