Technology Questions

Dalvik serves as a virtual machine, and it is where every Android application runs. Through Dalvik, a device is able to execute multiple virtual machines efficiently through better memory management.

The business analyst must understand IT and also has to understand the stakeholder’s needs. 

A systems analyst has the ability to look at a program or utility and see the code. They can go in and pinpoint where changes need to be made. 

Use case diagram, activity diagram, Collaboration diagram. 

Use case diagram :

It describes the business environment. Its primary goal is to show the series of events and actions within any given process that will be performed by an actor.  

Activity diagram:

The activity diagram is important because it gives an outline of the work flow within the business as well as the activities and action completed. 

For instance with a company, there is likely to be more than one department. In such a case each department, will have different access levels to the system. 

So if there’s a Medical, HR and Accounts team they will only have access to screens that relate to each. 

The activity diagram will highlight the differences within the departments which will be very helpful for developers when they are designing and coding. 

Collaboration diagram:

A collaboration diagram, also called a communication diagram or interaction diagram, is an illustration of the relationships and interactions among software objects in the Unified Modeling Language (UML). The concept is more than a decade old although it has been refined as modeling paradigms have evolved. 

The following are the areas of concern for tuning:

- Memory Usage

- Data Storage

- Data Manipulation

- Physical Storage

- Logic Storage

- Network Traffic

Tuning Memory Usage: In Oracle 10g, we can use the Automatic Workload Repository (AWR) toolset to gather and manage statistical data but in case of Oracle 11g, we can use new initialization parameters such as MEMORY_TARGET to further control the overall memory used by Oracle. It helps us to tune the database automatically when we don’t have time to read the AWR report.

Tuning Data Manipulation: There are two ways to tune Data manipulation in Oracle one way is through Conventional Path mode and second is Direct Path mode.

Tuning Physical Storage: We need to tune the physical storage because it limits the disk in database. This can be done by: Distributing I/O, Striping and Mirroring.

Verification: Verification is a process to ensure that the software that is made, matches the original design. In other words, it checks whether the software is made according to the criteria and specification described in the requirement document. It is to check whether you built the product right as per design. It is a low level checking. (It is done in walk-through meetings generally). It checked whether it is made accordingly to the design..

Validation: Validation is a process to check whether the product design fits the client’s need. It checks whether you built the right thing. It checks whether it is designed properly.

Constraints enable the RDBMS to enforce the integrity of the database automatically, without the need to create triggers, rule or defaults.

Types of Constraints: NOT NULL, CHEQUE, UNIQUE, PRIMARY KEY, FOREIGN KEY.

virtual LAN (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer (OSI layer 2). LAN is the abbreviation for local area network and in this context, virtual refers to a physical object recreated and altered by additional logic.

VLANs work by applying tags to network packets and handling these tags in networking systems – creating the appearance and functionality of network traffic that is physically on a single network but acts as if it is split between separate networks. In this way, VLANs can keep network applications separate despite being connected to the same physical network, and without requiring multiple sets of cabling and networking devices to be deployed.