Technology Questions

Number, String, Boolean, Function, Object, Null, Undefined.

1)standered table

2)index table

3)hashed table

4)sorted table

Intents are created to define an action that we want to perform and the launches the appropriate activity from another application.

Code

        Intent intent = new Intent(Intent.ACTION_SEND);

        intent.putExtra(Intent.EXTRA_EMAIL, recipientArray);

        startActivity(intent);

advantages: view is used to retrieve the data very fastly from the database tables
* memory wastage is reduced
* faster than joins to retrieve the data from database tables

disadvantages:
* view is not a container,it will not hold the data
* view memory is not permanent memory

A throw is used to throw an exception manually, where as throws is used in the case of checked exceptions, to tell the compiler that we haven't  handled the exception, so that the exception will be handled by the calling function.

Anonymous class is class without name.

EX:

class A {

}

class Demo {

    A r = new A() {

        }; //anonymous class

}

A unique constraint on a column uniquely identifies the record by a combination of one or more fields. Few unique constraint fields can have a NULL value as long as the combination of values is unique.

Example:
create table employee ( id number NOT NULL, dob DATE, professor_id NOT NULL, Name varchar(200) Constraint id_unique UNIQUE(id,dob) );

Joins are used to combine data of one or more tables. Joins should be used when there is abundant data. Joins can be LEFT, RIGHT, OUTER, INNER or even SELF JOIN. The purpose is to bind data from multiple tables without any receptivity