oracle sql interview questions

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 Q1.) What is the difference between DML and DDL?

Ans: DDL (Data Definition Language) is used mainly for defining the database schema. It consists of SQL statements which give an idea about the structure of the database. Some examples of DDL statements are:

CREATE: Used to create new database objects
ALTER: Used to alter characteristics of already existing database objects
DROP: Used to remove database objects
TRUNCATE: Used to remove all records including all spaces allocated to record from the table

RENAME: Used to rename any database object
DML (Data Manipulation Language) are responsible for managing and manipulating various data schemas or database objects. They cannot alter the characteristics of a database object unlike DDL statements. Most common examples are:

SELECT: Used to retrieve data from the database
INSERT: Used to insert new data/records into the database
UPDATE: Used to update/modify the existing data/record from the database
DELETE: Used to remove the existing data/record from the database

Q2.) What does NVL function does?

Ans: NVL function is mainly used to replace NULL values with some other value provided the data type of the NULL value to be replaced with the given value is same.

Q3.) What is a BLOB data type?

Ans: BLOB is a binary string of varying length used to store data up to 2 gigabytes. Images, videos and other documents can be stored in the database using BLOB data type.

Q4.) What is the difference between varchar and varchar2?

Ans: The data type varchar is used to stored data up to 2000 bytes while varchar2 is used to store data up to 4000 bytes. However, the prominent difference between varchar and varchar2 is that varchar can occupy NULL values while varchar2 cannot.

Q5.) What are the different Oracle SQL database objects?

Ans:    Tables - Database object used to store various database records
           Views - It is a virtual table derived from one or more tables
           Indexes - Used to improve efficiency and performance of the database
           Synonyms - Aliases used for database tables

Q6.) What are various types of integrity constraints in Oracle SQL?

Ans: Unique: It ensures that the given column or entity is unique and cannot     be duplicated.

Not NULL: It ensures that the given column cannot be empty.

Foreign: It ensures that the two entities/tables share a common key with the one in parent table being a primary key and the one in child table being a foreign key.

Q7.) What is a hash cluster?

Ans: It is used to store table in a manner that query fetching results in faster data retrieval by using the hashing technique.

Q8.) What is a sub query?

Ans: Sub query refers to a query written with in a query. It is often referred to as nested query or inner query. It is used to apply filters on selected data retrieved by the main query.

Q9.) What is an alert?

Ans: A window appearing in the center of the screen overlaying the current screen to provide some form of information is termed as an alert.

What You Will Learn In The Android Training Program

Android Training is most suggestive program for all candidates those who have been finished their graduation courses. Android training program is nothing but Android developing and it will describes the functionality that how to make the procedure to get develop the applications in various android mobiles. The installation structure involved on android mobiles are different for different users of mobile phones, so by going through training session of android program, candidates will come to know the details of entire procedure which illustrate the structure and assembling of applications and running method in the device which are accomplished with smart devices.

Android training classes can start through online classes where as it will illustrates the specific topic which was completely related to android developing. It will expand the information that will get into particular task with sample code and re use of applications in your devices itself. Entire program of android developing will be classified into various groups such as found in six sessions. Students can get into all those presenting sessions at any time during the period of course as per their utility and understanding status. Institute or developers will assign the session of each for particular period of time and then made the session implement once the step of first session has been finished then went for next phase of training.

After successful come over across all sessions of android develop training, candidates will get a perfect awareness about the program and also they can easily get into the portion of new development technique without any distortion. Various sites of training programs are available now days and going through online classes are easiest task than direct presence to institutes. Having training through online program is simple than going through offline classes at various places. Sitting at one place and go through the training session by using internet connection.

Go through same developer program that illustrates the details of Android training for every day program. At first session, trainers will suggest the steps of essentials for android application development and they are going to new version of android application developer that should finish the classes in specified order. Video classes as well as audio classes are made available in online, so user can choose any of those as per their interest and convenience.

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Future Career Prospect Of MSBI

career opportunities in msbi

Microsoft Business Intelligence is the powerful business tool designed by Microsoft that offers excellent solutions for queries related to Business Intelligence and Data Mining.  This tool makes use of Microsoft Visual Studio Data Tools along with SQL Server.

Importance of MSBI:
MSBI allows the user to access the updated and accurate data which in turn facilitates proper decision making in the organisation. Different processes to be taken up in business intelligence require different set of tools for the solutions and MSBI provides the user with different tools to accomplish the task. It has an important application in Online Transaction Processing.

Business Intelligence has a very important role in almost all sorts of business in future. The obvious reason being handling of big data, its analysis and making smart decisions related to organisation is involved in every sector being IT, Engineering, Architecture, Banking, Government and Private agencies etc… and MSBI serves all the necessary requirements of BI

Future Aspects With MSBI

The business are now spread globally. The customer demands are increasing and to satisfy them and stay in the competitive environment successfully Business Intelligence is foremost requirement. Its perspectives in the future are detailed as follows:

Forecasting Using MSBI:

MSBI uses data mining tools and Predictive Analysis being the branch of data mining is beneficial in making future predictions by the analysis of present and the past data. The tool can help the organisations to work on their drawbacks, keep up with the strengths, understand the requirement of the customers in a better way and reduce the chances of occurrence of any loss and maximise the profit.

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Example showing Why MSBI?

We should comprehend this photo by taking a case of an association. We should take the case :- Calvin Klein (CK). We have outlets of Calvin Klein (CK) in many parts of India. Each outlet stores their client information in their separate database and it's not obligatory that each outlet is utilizing a similar database. A few outlets may have Sybase as their database, some may utilize prophet or a few stores incline toward putting away their information in basic content documents. 

Before continuing ahead with our clarification, we ought to know "what OLTP is"? It remains for Online Transaction Processing. These are essentially the online exchanges (Insert, Update, Delete) performed on database at each outlet by the client.

In the wake of putting away day by day information of the clients who went by Calvin Klein outlet at various stores, the information is then incorporated and spared it in a brought together database. This is finished with the assistance of OLTP part of MS SQL Server. Incorporation implies converging of information from various information stores (i.e. it might be a level document, Excel sheets, Sybase, Oracle, and so on.), invigorating information in information distribution centers and to rinse information (e.g. - Date arrangement might be diverse for various outlet's database, so same organization is made to make it even) before stacking to expel mistakes. Presently, you should be clear with the Integration idea. This is our Phase 1-"SSIS". 

msbi courses in bangalore

Next stride is to break down the put away unified information. This tremendous information is then isolated into Data Marts on which logical process is gone ahead. Investigation administrations utilize OLAP (Online Analytical Processing) segment and information mining abilities. It permits to fabricate multi-dimensional structures called CUBES to pre figure and store complex conglomerations, and furthermore to manufacture mining models to perform information examination which distinguishes significant data like what are the current patterns, designs, abhorrences of clients. Business examiner then perform information mining capacity on multi dimensional solid shape structure to look information from alternate points of view. Multi Dimensional investigation of gigantic information finishes the Phase 2-"SSAS". 

msbi courses in bangalore

Presently, the main thing left is to speak to this examination graphically so that an association (Calvin Klein) can settle on viable choice to improve their income, increase most extreme benefit and to decrease time wastage. Along these lines, this is done in types of Reports, Scorecards, Plans, Dashboards, Excel exercise manuals, and so on. This information reports will tell the association what is the income of Calvin Klein in particular time at particular place, where they caught the market, in which part they are missing and needs to support up and numerous different things which end clients wish to investigate. This detailing is finished with an instrument SQL Server Reporting Services and finishes Phase 3 – "SSRS".

This finishes our chart and i trust that you are presently evident with the parts of MSBI. We will get into the center in our later instructional exercises of MSBI.

For More Information: MSBI Training Cost in Bangalore

What is MSBI - Microsoft Business Intelligence

What is MSBI

 

MSBI remains for Microsoft Business Intelligence. This intense suite is made out of tools which helps in giving best answers for Business Intelligence and Data Mining Queries. This tools utilizes Visual studio alongside SQL server. It enable clients to access precise and progressive data for better basic leadership in an association. It offers distinctive tools for various procedures which are required in Business Intelligence (BI) arrangements. 

MSBI Training in Bangalore

MSBI is isolated into 3 classifications:-

1. SSIS – SQL Server Integration Services
2. SSAS – SQL Server Analytical Services
3. SSRS – SQL Server Reporting Services

1. SSIS– SQL Server Integration Services :- SSIS: (Sql Server Integration Services) This tool is utilized for the coordination like tricking the information starting with one database then onto the next like from Oracle to SQL Server or from Excel to Sql Server and so on. This device is likewise utilized for mass exchanges in the database like embeddings lac's of records without a moment's delay. We can make the mix administrations modules which will carry out the employment adversary us.

2. SSAS– SQL Server Analytical Services - SSAS: (SQL Server Analysis Services) This apparatus is utilized to break down the execution of the sql server as far as load adjusting, overwhelming information, tranasction and so forth. So it is pretty much identified with adminsitration of the SQL Sevrer utilizing this device. This is intense instrument and through this we can examine the information embeddings into the database like what number of exchanges occurs in a moment and so forth.

3. SSRS– SQL Server Reporting Services - SSRS(SQL Server Reporting Services) This apparatus is identified with the era of report. This is exceptionally productive device as it is stage autonomous. We can produce the report utilizing this device and can use in an applications. Presently a days this is exceptionally prevalent in the market.

Few of the advantages of MSBI

1. Easy Data Exploration and Visualization
2. Managed Self-service BI tool
3. Full Use Of Native Excel Features
4. Dashboards And Scorecards
5. MSBI Support To Web Services
6. Complete End to End Business Solutions
7. MSBI Supports Data warehousing Applications

For More Information: MSBI Training Institutes in Bangalore