I have a database with 5 millions records, i have Person table having 5 million records and its have 13 columns. Forename and surname column is heavily populated as compared to other columns. My question is it appropriate to separate forename and surname column and make separate tables for it and reference it with id in person_detail table. What are the advantages and disadvantages in separating these...

prakash

• Mar 9th, 2019

Advantage: Size of the table will decrease and so the query performance will be improved.
Disadvantage: Join query will be required to get surname and full name of person.

Asiimwe

• Jan 2nd, 2016

Its not good to separate them.

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How to get nth record from index by table?

vadivelraju

• Feb 17th, 2019

We can get like collection(n).column [Ex. emp(3).empno]

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Lavanish Chaudhary

• Jul 1st, 2018

A database view is a searchable object in a database that is defined by a query. Types of view in a database management system:
A. Simple view
B. Complex view
C. Readable view
D. Force view
E. Materialized view
F. Inline view

Nagaraj

• Nov 13th, 2017

1. Updatable view & Non-updatable view
2. Simple view & complex view
3. Read only view
4. Force view
5. Meterialized view
6. Inline View

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What is the difference between MS SQL Server and SQL Server? Are both same are not?

Mayank Sanghvi

• Mar 21st, 2018

Both are same. MS SQL Server means Microsoft SQL Server. SQL Server is the database developed by Microsoft. Because of this it is also known as MS SQL Server.

justin

• Dec 26th, 2017

Both are same

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At what trigger timing does mutating trigger error occur?
Is it before/after or both? And is it for row level/statement level OR both?

Achyuth

• Oct 30th, 2017

When trying update a record by using a trigger which is already in use

anjali

• Mar 8th, 2017

The mutating error comes when we use a column in our trigger and we want to update it at the same time. It occurs in row level triggers irrespective of the fact whether it is before or after trigger.

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ZAHID

• Nov 20th, 2016

Three Components:
1. Data Structure (Data organization in the form of table with row and table)
2. Data Manipulation (Operation perform(using SQL) on data stored in relation)
3. Data Integrity (Maintain data stored in relation for long time)

Sandhya.Kishan

 Profile Answers by Sandhya.Kishan Questions by Sandhya.Kishan

• Jul 6th, 2012

The Relational model contains 3 components 1)set of relations and set of domains ( data structure).
2)Integrity rules (data integrity) and
3)The operation that can be operate on the data (data manipulation).

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Amit

• Aug 28th, 2016

Adding 2 cents 1) DELETE is DML command because it does not change data dictionary (Every command which changes data dictionary tables is called DDL command ) TRUNCATE is DDL command is changes stor...

Ashakant Kendre

• May 9th, 2016

1>TRUNCATE is a DDL command whereas DELETE is a DML command. 2>TRUNCATE is much faster than DELETE. Reason: When you type DELETE. All the data get copied into the Rollback Tablespace first, then del...

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Read Best Answer

Editorial / Best Answer

letsconverse  

 Profile Answers by letsconverse Questions by letsconverse

• Member Since Sep-2009 | Sep 21st, 2009

---

This one is better I guess:

query:

SELECT ((count(DECODE(to_char(hire_date,'YYYY'), 1995, 'c1')) )+(count(DECODE(to_char(hire_date,'YYYY'), 1996, 'c2')))+(count(DECODE(to_char(hire_date,'YYYY'), 1997, 'c3')))+(count(DECODE(to_char(hire_date,'YYYY'), 1998, 'c4')))) as TOTAL,
count(DECODE(to_char(hire_date,'YYYY'), 1995, 'c1')) "1995",
count(DECODE(to_char(hire_date,'YYYY'), 1996, 'c2')) "1996",
count(DECODE(to_char(hire_date,'YYYY'), 1997, 'c3')) "1997",
count(DECODE(to_char(hire_date,'YYYY'), 1998, 'c4')) "1998"
FROM employees;

Results for the above query is like:

     TOTAL       1995       1996       1997       1998
  ----------   ----------   ----------  ----------  ----------
          65             4            10           28           23

Revert if you have a question. I'll try.
NOTE: You may want to change the spl characters and the years based on your requiremnet.

Thanks

serine

• Aug 26th, 2016

Why did we use c1?

ashwini

• Jun 22nd, 2015

Can anybody tell me how to get the count of the test cases that was run by a person?

Improve Answer

Display 6th & 9th records only from the table using ROWNUM & MINUS & UNION ?

ramesh

• May 26th, 2016

Using Rownum we cannot display records but using set operation like minus and union then we can display the records if conditions is satisfied.

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qptopm

 Profile Answers by qptopm Questions by qptopm

• Apr 26th, 2016

Database Server - Database server will have your one or more database hosted such as Oracle, Sql Server, MySql, etc.A database is a collection of information that is organized so that it can easily b...

HARENDRA KUMAR SINGH

• Mar 5th, 2016

Database is used to store collection of data.
Database Server is collection of database stored separately.

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Why is RowSet implementation is beneficial over ResultSet?

sunil

• Mar 14th, 2016

How to execute the JDBC example using JdbcRowSet instead of Using ResultSet?

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amir ali

• Nov 23rd, 2015

Views are dependent on data tables.

PADMINI M

• Nov 16th, 2015

Correct answer is it depends.
Any modifications, including UPDATE, INSERT, and DELETE statements, must reference columns from only one base table
Only we can update a view in one base table.

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viswanath

• Aug 23rd, 2015

I did not found any "demobld.sql" in my system, then how can import default tables ?

smartrameshdwh

• Apr 4th, 2007

step1) Search "demobld.sql" file in the directory where you installed Oracle using Search option. step2) Make a copy of it (demobld.sql) in C drive or D drive step3)Execute "@c:demobld....

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Consider an organization by which you are familiar. If the organization is using file processing system then what are the problems organization will face?Explain with suitable examples.

sunil

• Aug 3rd, 2015

1-Redundancy
2-Consistency
3-Security
4-Automaticity of update
and many more

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Sharath

• Jun 8th, 2015

Select ename ,count(ename) from emp group by ename

ashbittu

 Profile Answers by ashbittu Questions by ashbittu

• Jun 1st, 2015

Code
 

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Why session is created ?
How is it related to security concern for the application?
Why session ID is created ?

Gaurav.khurana

 Profile Answers by Gaurav.khurana Questions by Gaurav.khurana

• May 9th, 2015

Its like to maintain some information during a particular conversation. Suppose you open gmail so some information has to be maintain during the whole conversation with server from browser(client) ..
So that information is stored somewhere till the time you logout.(example)

abha maurya

• Apr 18th, 2015

Session creation ?is very important for security purpose....suppose various people on the same website trying to fill form so how does server understand the request of diff. Users that's why we use s...

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Login Screen

User ID -> textbox
Password -> textbox

Sign in-> button..

Can someone send me how to write test cases for the above requirement?

Haritha

• Apr 17th, 2015

Enter Blank details and click on sign in button
Enter valid user name,Invalid password and click on sign in button
Enter Invalid user name ,valid password and click on sign in button
Enter Both invalid details and click on sign in button
Enter Valid User name& password click on sign in button

msrajeshreddy

• Oct 25th, 2013

1.enter valid username and valid password.
2.enter invalid username and valid password.
3.enter invalid username and invalid password.
4.enter blank username and valid password.
5.enter valid username and blank password.
6.enter blank username and blank password.

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Differentiate between Controlled and Uncontrolled Redundancy

Azad

• Feb 13th, 2015

Drawback of traditional file system

supriya_pict

 Profile Answers by supriya_pict Questions by supriya_pict

• Sep 11th, 2009

Redundancy is Direct if a value is a copy of another Indirect if the value can be derived from other values: Simplifies retrieval but complicates update Conversely integration makes...

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Nirali Dedhia

• Aug 15th, 2014

State and explain categories os specialization?

Gajanan K

• Jul 13th, 2007

Aggregation: Selecting the data in group of records is called aggregation. There are five aggregate system functions they are viz. Sum, Min, Max, Avg, Count. They all have their own purpose Decomp...

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Why is the choice of primary key important and are three characteristics of an ideal primary key?

sanit kale

• Apr 24th, 2014

The PRIMARY KEY constraint uniquely identifies each record in a database table.

Primary keys must contain unique values.

A primary key column cannot contain NULL values.

Each table should have a primary key, and each table can have only ONE primary key.

chaitra murthy

 Profile Answers by chaitra murthy Questions by chaitra murthy

• Jan 16th, 2009

Primary key will let the retrieval operation to be fast.It will not allow you to insert duplicate and null values.It is used to uniquely identify a row in a table.

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