//***************************************************************************
// (c) Copyright IBM Corp. 2007 All rights reserved.
// 
// The following sample of source code ("Sample") is owned by International 
// Business Machines Corporation or one of its subsidiaries ("IBM") and is 
// copyrighted and licensed, not sold. You may use, copy, modify, and 
// distribute the Sample in any form without payment to IBM, for the purpose of 
// assisting you in the development of your applications.
// 
// The Sample code is provided to you on an "AS IS" basis, without warranty of 
// any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR 
// IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do 
// not allow for the exclusion or limitation of implied warranties, so the above 
// limitations or exclusions may not apply to you. IBM shall not be liable for 
// any damages you suffer as a result of using, copying, modifying or 
// distributing the Sample, even if IBM has been advised of the possibility of 
// such damages.
//***************************************************************************
//
// SOURCE FILE NAME: TbCompress.sqlj
//
// SAMPLE: How to create tables with null and default value compression 
//         option. 
//
// SQL STATEMENTS USED:
//         CREATE TABLE 
//         ALTER TABLE
//         DROP TABLE
//         COMMIT
//
// Classes used from Util.java are:
//        Db
//        SqljException
//
//                           
// Output will vary depending on the JDBC driver connectivity used.
//***************************************************************************
//
// For more information on the sample programs, see the README file.
//
// For information on developing Java applications see the Developing Java Applications book.
//
// For information on using SQL statements, see the SQL Reference.
//
// For the latest information on programming, compiling, and running DB2
// applications, visit the DB2 Information Center at
//     http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/index.jsp
//***************************************************************************

import java.lang.*;
import java.sql.*;
import sqlj.runtime.*;
import sqlj.runtime.ref.*;

class TbCompress
{
  public static void main(String argv[])
  {
    DefaultContext ctx = null;

    try
    {
      Db db = new Db(argv);

      System.out.println();
      System.out.println(
        "THIS SAMPLE SHOWS HOW TO USE NULL AND DEFAULT VALUE\n" + 
        "COMPRESSION OPTION AT TABLE LEVEL AND COLUMN LEVEL \n");

      // connect to the 'sample' database
      ctx = db.getDefaultContext();
      
      // create a new table
      tbCreate();
      
      // activate null and default value compression
      tbCompress();
      
      // drop the table created
      tbDrop();

      // disconnect from 'sample' database
      db.disconnect();
    }
    catch (Exception e)
    {
      SqljException sqljExc = new SqljException(e);
      sqljExc.handle();
    }
  } // main

  // Create a new table
  static void tbCreate()
  {
    try
    {       
      // create base table
      System.out.println(
        "\n-----------------------------------------------------------\n" +
        "USE THE SQL STATEMENT\n" +
        "  CREATE TABLE\n" +
        "TO CREATE A TABLE\n\n" +
        "  CREATE TABLE comp_tab(col1 INT NOT NULL WITH DEFAULT,\n" + 
        "                        col2 CHAR(7),\n" +
        "                        col3 VARCHAR(7) NOT NULL,\n" +
        "                        col4 DOUBLE) \n");     
           
      #sql {CREATE TABLE comp_tab(col1 INT NOT NULL WITH DEFAULT,
                                  col2 CHAR(7),
                                  col3 VARCHAR(7) NOT NULL,
                                  col4 DOUBLE)};
 
      System.out.println("  COMMIT"); 
      #sql {COMMIT};                             
    }
    catch (Exception e)
    {
      SqljException sqljExc = new SqljException(e);
      sqljExc.handle();
    } 
  } // tbCreate
  
  // Activate null and default value compression
  static void tbCompress()
  {
    try
    {       
      System.out.println(
        "\n-----------------------------------------------------------\n" +
        "USE THE SQL STATEMENT \n" +
        "  ALTER TABLE\n" +
        "TO ALTER COMPRESSION OPTIONS OF THE TABLE\n\n" +
        "To activate VALUE COMPRESSION at table level and COMPRESS \n" +
        "SYSTEM DEFAULT at column level \n\n" +
        "  ALTER TABLE comp_tab ACTIVATE VALUE COMPRESSION \n\n" +
        "Rows will be formatted using the new row format on subsequent\n" +
        "insert, load and update operation, and NULL values will not be\n" +
        "taking up space if applicable.\n");

      #sql {ALTER TABLE comp_tab ACTIVATE VALUE COMPRESSION};
      #sql {COMMIT};
      
      // if the table comp_tab does not have many NULL values, enabling
      // compression will result in using more disk space than using 
      // the old row format 
        
      System.out.println(
        "\nTo save more disk space on system default value for column\n" +
        "col1, enter\n" +
        "\n  ALTER TABLE comp_tab ALTER col1 COMPRESS SYSTEM DEFAULT\n" +
        "\nOn subsequent insert, load, and update operations, numerical\n" +
        "0 value (occupying 4 bytes of storage) for column col1 will\n" +
        "not be saved on disk.\n"); 
      
      #sql {ALTER TABLE comp_tab ALTER col1 COMPRESS SYSTEM DEFAULT};
      #sql {COMMIT};
      
      System.out.println(
        "\nTo switch the table to use the old format, enter\n\n" +
        "  ALTER TABLE comp_tab DEACTIVATE VALUE COMPRESSION\n\n" +
        "Rows inserted, loaded or updated after the ALTER statement\n" +
        "will have old row format.\n");  
        
      #sql {ALTER TABLE comp_tab DEACTIVATE VALUE COMPRESSION};
      #sql {COMMIT};
    }
    catch (Exception e)
    {
      SqljException sqljExc = new SqljException(e);
      sqljExc.handle();
    } 
  } // tbCompress

  // Drop the table created
  static void tbDrop()
  {
    try
    {              
      // drop the table
      System.out.println(
        "\n-----------------------------------------------------------" +
        "\nUSE THE SQL STATEMENT\n" +
        "  DROP TABLE\n" +
        "TO DROP THE TABLE\n\n" +
        "  DROP TABLE comp_tab\n" +
        "\n  COMMIT");
         
      #sql {DROP TABLE comp_tab};
      #sql {COMMIT};
    }
    catch (Exception e)
    {
      SqljException sqljExc = new SqljException(e);
      sqljExc.handle();
    } 
  } // tbDrop
} // TbCompress