SELECT query {EXPLAIN | DESCRIBE | DESC} We usually use this command to check to see if how many rows the query goes through. Especially for the INDEX column checking. Search LIKE '%key%' consumes more resource than LIKE 'key%' Denormalisation This database design helps to speed up the data reading. Because the SQL query no need to join data between tables.
Singleton design pattern This pattern makes sure only one object is created and used though out the system. Create a static instance in the single class public class SingleObject { //create an object of SingleObject private static SingleObject instance = new SingleObject (); //make the constructor private so that this class cannot be //instantiated private SingleObject (){} //Get the only object available public static SingleObject getInstance (){ return instance ; } public void showMessage (){ System . out . println ( "Hello World!" ); } } Use this instance through the system. public class SingletonPatternDemo { public static void main ( String [] args ) { //illegal construct //Compile Time Error: The constructor SingleObject() is not visible //SingleObject object = new SingleObject(); //Get the only object available SingleObject object = S