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Friday, August 30, 2013

Mysql Upgrade upgrade and bugfix

After upgrading MySQL from version 5.0 to 5.5 I started getting the following message trying to edit table structure in Navicat:

Cannot load from mysql.proc.
The table is probably corrupted Luckily there is an easy fix.

Run the following command from the command prompt (on Windows you might need to run it from MySQL's bin directory).

mysql_upgrade

In some cases you will need specify

mysql root password and --force option (if you run upgrade procedure already).

mysql_upgrade -u root -p --force

Thursday, August 29, 2013

Complete remove Mysql

sudo apt-get remove mysql-server mysql-client mysql-common
sudo apt-get purge mysql-server mysql-client mysql-common
sudo apt-get autoremove
 
locate mysql (get lla location where install mysql and delete) 

Saturday, August 24, 2013

java resultset insert, update and delete

//STEP 1. Import required packages
import java.sql.*;

public class JDBCExample {
   // JDBC driver name and database URL
   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
   static final String DB_URL = "jdbc:mysql://localhost/EMP";

   //  Database credentials
   static final String USER = "username";
   static final String PASS = "password";
   
 public static void main(String[] args) {
   Connection conn = null;
   try{
      //STEP 2: Register JDBC driver
      Class.forName("com.mysql.jdbc.Driver");

      //STEP 3: Open a connection
      System.out.println("Connecting to database...");
      conn = DriverManager.getConnection(DB_URL,USER,PASS);

      //STEP 4: Execute a query to create statment with
      // required arguments for RS example.
      System.out.println("Creating statement...");
      Statement stmt = conn.createStatement(
                           ResultSet.TYPE_SCROLL_INSENSITIVE,
                           ResultSet.CONCUR_UPDATABLE);
     //STEP 5: Execute a query
      String sql = "SELECT id, first, last, age FROM Employees";
      ResultSet rs = stmt.executeQuery(sql);

      System.out.println("List result set for reference....");
      printRs(rs);

      //STEP 6: Loop through result set and add 5 in age
      //Move to BFR postion so while-loop works properly
      rs.beforeFirst();
      //STEP 7: Extract data from result set
      while(rs.next()){
         //Retrieve by column name
         int newAge = rs.getInt("age") + 5;
         rs.updateDouble( "age", newAge );
         rs.updateRow();
      }
      System.out.println("List result set showing new ages...");
      printRs(rs);
      // Insert a record into the table.
      //Move to insert row and add column data with updateXXX()
      System.out.println("Inserting a new record...");
      rs.moveToInsertRow();
      rs.updateInt("id",104);
      rs.updateString("first","John");
      rs.updateString("last","Paul");
      rs.updateInt("age",40);
      //Commit row
      rs.insertRow();

      System.out.println("List result set showing new set...");
      printRs(rs);
      
      // Delete second record from the table.
      // Set position to second record first
      rs.absolute( 2 );
      System.out.println("List the record before deleting...");
      //Retrieve by column name
      int id  = rs.getInt("id");
      int age = rs.getInt("age");
      String first = rs.getString("first");
      String last = rs.getString("last");

      //Display values
      System.out.print("ID: " + id);
      System.out.print(", Age: " + age);
      System.out.print(", First: " + first);
      System.out.println(", Last: " + last);

     //Delete row
      rs.deleteRow();
      System.out.println("List result set after \
                                 deleting one records...");
      printRs(rs);

      //STEP 8: Clean-up environment
      rs.close();
      stmt.close();
      conn.close();
   }catch(SQLException se){
      //Handle errors for JDBC
      se.printStackTrace();
   }catch(Exception e){
      //Handle errors for Class.forName
      e.printStackTrace();
   }finally{
      //finally block used to close resources
      try{
         if(conn!=null)
            conn.close();
      }catch(SQLException se){
         se.printStackTrace();
      }//end finally try
   }//end try
   System.out.println("Goodbye!");
}//end main

   public static void printRs(ResultSet rs) throws SQLException{
      //Ensure we start with first row
      rs.beforeFirst();
      while(rs.next()){
         //Retrieve by column name
         int id  = rs.getInt("id");
         int age = rs.getInt("age");
         String first = rs.getString("first");
         String last = rs.getString("last");

         //Display values
         System.out.print("ID: " + id);
         System.out.print(", Age: " + age);
         System.out.print(", First: " + first);
         System.out.println(", Last: " + last);
     }
     System.out.println();
   }//end printRs()
}//end JDBCExample