Vijay

• Mar 20th, 2013

By using merge statement we can do it simply.

smi

• Jul 30th, 2012

Use merge stat

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aytasirs

• Apr 29th, 2013

Yes We can. If we use the combination "unique+not null" the referential integrity is not maintained and that is not the case with primary key.

EHSAN REHMANI

• Apr 27th, 2013

There is only one primary key per table but we can use unique and not null constraints more than one column in a table. Primary key having both functionality as it can not be null but unique.

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What are Pair Wise & Non-Pair Wise Columns?

Vinod Tuteja

• Jun 6th, 2013

NON PAIRWISE COMPARISON SUBQUERY: "sql SELECT employee_id, manager_id, department_id FROM employees WHERE manager_id IN (SELECT manager_id FROM employ...

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Ehsan Rehmani

• Aug 7th, 2013

The set transaction statement used to establish the current transaction as read only or read write, establish its isolation level or assign it to a specified rollback segment or when someone use DDL statement.

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HAVING clause is used when you want to specify a condition for a group function and it is written after GROUP BY clause. The WHERE clause is used when you want to specify a condition for columns, single row functions except group functions and it is written before GROUP BY clause if it is used.

Mushtaque

• Aug 25th, 2013

WHERE clause can contains condition that must be met and should directly follow the from clause. And HAVING clause can precede GROUP BY clause,but it is more logical to declared in after GROUP BY clau...

Santhoshkandula

 Profile Answers by Santhoshkandula Questions by Santhoshkandula

• May 11th, 2011

?? we have to?apply the condition?Before grouping the records then you have to?use WHERE clause.?? we have to apply the condition after grouping the records then you have to apply HAVING clause.? Thanks & Regards??? K.Santhosh

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ambika

• Oct 21st, 2013

Recovery in centralized dbms

su4surya

 Profile Answers by su4surya Questions by su4surya

• Aug 24th, 2009

A centralized database has all its data at one place so there may occur problems of data avalability, and a system crash may lead to whole dataloss. In a distributed database, database is stored on se...

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srini

 Profile Answers by srini Questions by srini

• Dec 6th, 2013

Using PIVOT we can do this:

http://www.dba-oracle.com/t_pivot_examples.htm

VIJAY SHARMA

• Sep 24th, 2012

SELECT SYS_CONNECT_BY_PATH(DEPTNO, )I ,
SYS_CONNECT_BY_PATH(DNAME, ) II,
SYS_CONNECT_BY_PATH(LOC, ) III
FROM DEPT
WHERE LEVEL = &TOTALDEPARTMENTS
START WITH DEPTNO = 10
CONNECT BY PRIOR DEPTNO < DEPTNO;

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What is the literal meaning of SQL

bhagare

 Profile Answers by bhagare Questions by bhagare

• Feb 5th, 2014

Structure quary launguge

nagarjuna

• Nov 21st, 2013

The terms literal and constant value are synonymous and refer to a fixed data value.For example, JACK, BLUE ISLAND, and 101 are all character literals

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How to convert rows in column using SQL in Oracle;
for example
sl_no
1
2
3
4
output is 1234;

How to convert one column value into rows using SQL
for example
employee_name
Kumar

output
K
u
m
a
r

Megamind

 Profile Answers by Megamind Questions by Megamind

• Apr 14th, 2014

We can do it via pivot keyword..... it will change the row into column.. its simply a pseudo column

Kandavel Durairaj

• Nov 8th, 2013

Using LISTAGG. Read the oracle documentation for more info.

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AiM

• Aug 23rd, 2014

Trigger code to create a trigger in disable mode starting 11g "oracle create or replace trigger prac_trig_emp1 before insert or update OR DELETE ON emp1 REFERENCING NEW AS NEW OLD...

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jomarie

• Sep 2nd, 2014

This is formed when join conditions is omitted or invalid

sampra

 Profile Answers by sampra Questions by sampra

• Feb 26th, 2008

When a join condition is omited when getting  result from two tables then that kind of query gives us Cartesian product, in which all combination of rows displayed. All rows in the first table is joined to all rows of second table......

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kitty

• Sep 8th, 2014

Can u plz explain me in detail about the answer you have provided with correlated sub query.

Thnks in advance !

yagneswarasankar

 Profile Answers by yagneswarasankar Questions by yagneswarasankar

• Dec 2nd, 2010

4th Highest Salary  1*  select a.last_name,a.salary from (select b.*,rownum rn from (select last_name,salary from employees order by salary desc)b)a where rn = &nSQL> /Enter value for...

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sanjay pradhan

• Sep 26th, 2014

Alter trigger trigger_name disable

vijaya

• May 11th, 2013

Alter trigger trigger_name disable/enable all triggers.

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TABLESVIEWSINDEXESSYNONYMSSEQUENCESTABLESPACES etc

suresh

• Mar 13th, 2015

Table,view,procedure,function,package,synonums,triggers,index,sequencess

ankitagujrati28

 Profile Answers by ankitagujrati28 Questions by ankitagujrati28

• Apr 30th, 2010

There are 5 objects:-1.Table2.View3.Synonyms4.Sequences5.Index

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I have table with col1 values , col2 1st row value should be same col1 1st row, then col 2 row onwards row each should added each row values eg: col1 values 10,20,30. Etc, in col2 values display like 10, 30,60 etc. how we can write sql query ?

roshan.gwr

 Profile Answers by roshan.gwr Questions by roshan.gwr

• Mar 13th, 2015

Using Lag we can get it.
Select col1,col1+lag(col1,1,0) over (order by col1) col2 from table;

Vinod Kumar G M

• Nov 7th, 2014

SELECT COL_NAME , SUM(COL_NAME) OVER ( ORDER BY COL_NAME) FROM TABLE_NAME

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Name

• Mar 23rd, 2015

Nope. Thats SQL server.

mukeshkoshym

 Profile Answers by mukeshkoshym Questions by mukeshkoshym

• Nov 26th, 2009

In simpleVarchar2 works with 8 bit characters where as Nvarchar2 works ith 16 bit characters.If you have to store data other than english prefer Nvarchar2 or viceversa.

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ID employee department manager----------------------------------------------1 Suresh c++ NULL 2 Suresh c++ NUll3 Suresh c++ 25 Sarathy testing 26 Rajaraman c# 17 joe Flash 1I have the employee detail table ,In that i want to find the manager for each employee .The employee...

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Editorial / Best Answer

mktiwary  

 Profile Answers by mktiwary Questions by mktiwary

• Member Since Jun-2008 | Jun 6th, 2008

---

If you take the normal Oracle Employee (emp) table which consists of columns such as Employee Number (EMPNO) and Manager Number (MGR) then the query to find managers for all the employee is:

select e.ename as Employee, m.ename as Manager from emp e, emp m
where e.MGR = m.EMPNO

Nivetha Thinakaran

 Profile Answers by Nivetha Thinakaran Questions by Nivetha Thinakaran

• May 6th, 2015

Code
 

poojamohan

 Profile Answers by poojamohan Questions by poojamohan

• Sep 25th, 2012

How to get the old manager name ,if the employee has been changed to other manager?

Improve Answer

upendra

• Jun 11th, 2015

Sub Query: Inner query is executed first then it gives to outer query and outer query is executed.

Correlated Query: Outer query executed first row by row then it based on inner query is executed.

hindol_saha

 Profile Answers by hindol_saha Questions by hindol_saha

• Feb 24th, 2010

subquery : returns value to main query. it wont get values from main query. Example: SELECT id "Emp #" First_name "Name" salary "Salary" ROWNUM rank FROM (SELECT id first...

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How can I select column values from a table without knowing the column name ?Suppose , select employee_id from employees , now I don't know the column name and I want to select the column.Please let me know the answer

suganthi

• Jul 3rd, 2015

How to display data from table values without using select command?

kranthiswaroop

 Profile Answers by kranthiswaroop Questions by kranthiswaroop

• May 6th, 2014

Hi Sanjoy, Its a simple logic that, one should have complete idea about the Table , Table fields and data types used.. before applying any DML DCL DDL Commands, a programmer shoud know this. A progra...

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If in a table we dont use primary key or any other unique key then how to avoid duplication of data?

PremG

• Aug 10th, 2015

Yes, by creating Unique index on the respective column we can avoid duplicate values into that particular column. But, with this NULL values can not be restricted.

prakash

• Aug 6th, 2015

By creating unique index it is possible

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