Query to select distinct values without using distinct

Ashok

• Mar 21st, 2016

There are four ways for this.
1. Using distinct keyword
2. Using group by on all columns
3. Using Union operator
4. Using Analytical functions

Akshay Kadam

• Mar 27th, 2015

SELECT DISTINCT LASTNAME FIRSTNAME
FROM EMP;

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How to date track 2 tables to a previous month, using SQL code

suman

• Mar 18th, 2016

Date Track allows you to maintain a continuous history of the record or information over a period of time. You can use date track history to view a report of every update ever made to a record. Whene...

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Oracle does not allow a user to specifically locate tables, since that is a part of the function of the RDBMS. However, for the purpose of increasing performance, oracle allows a developer to create a CLUSTER. A CLUSTER provides a means for storing data from different tables together for faster retrieval than if the table placement were left to the RDBMS.

sumanamara2016

 Profile Answers by sumanamara2016 Questions by sumanamara2016

• Mar 18th, 2016

CLUSTERS A cluster is a schema object that contains data from one or more tables If you two are more tables are joined together on a single column and most of the time you issue join queries on ...

VIKRAM

• Dec 18th, 2015

In this case does the cluster avoid the JOIN Condition or not?

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Write SQL Query to find the department (ID) wise counts in the company.
Schema "employee" contains "employee_id", "employee_name", "dept_id".

sumanamara2016

 Profile Answers by sumanamara2016 Questions by sumanamara2016

• Mar 18th, 2016

"sql WITH EMP2 AS( SELECT DEPTNO,COUNT(*) LASAL FROM EMP GROUP BY DEPTNO) SELECT E.EMPNO,E.ENAME,E.DEPTNO,E2.LASAL FROM EMP E ,(SELECT * FROM EMP2) E2 WHERE E.DEP...

M JAGADADEESH

• Mar 10th, 2016

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Hi,

Let us take a scenario such that I issue a delete on table emp and truncate on table emp1 which is exact replica (in terms of both structure and data) of emp table.Now , I issue a commit on both sessions.

If I do a select * from emp and select * from emp1 now, which one should execute faster and why?

sumanamara2016

 Profile Answers by sumanamara2016 Questions by sumanamara2016

• Mar 18th, 2016

TRUNCATE TRUNCATE does not return number of deleted rows. TRUNCATE TABLE always locks the table and page but not each row. DELETE When we have to use DELETE Command then the data deleted can be ...

Mohammad Mansoor

• Feb 24th, 2016

Truncate and Drop commands Rollback is not possible for Table, whereas Delete Command we rollback the Data

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The variables declared in the procedure and which are passed, as arguments are called actual, the parameters in the procedure declaration. Actual parameters contain the values that are passed to a procedure and receive results. Formal parameters are the placeholders for the values of actual parameters

srinivas

• Feb 6th, 2016

How can I differentiate local veritable and formal parameter? In class I have variable called a, in that class one method has formal parameter is "a" and another local variable also "a".

Ravindra Kumar

• Dec 7th, 2015

The actual parameter is when you actually pass real value in calling that function. And, the formal parameter is the parameter as defined on the function signature.

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I am trying to get second highest age from the student table.Student table:SQL> desc student; Name Null? Type ----------------------------------------- -------- ----------------- ROLLNO NUMBER NAME VARCHAR2(20) AGE NUMBERAnd...

Sunil Badam

• Jan 29th, 2016

We can use rank function with partition by. It is very simple to use.

Code
 

Neeraj

• Jan 7th, 2016

Code
 

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Bibhuprasad Behera

• Dec 4th, 2015

Can you please send me the example of the trigger?

Nivetha Thinakaran

 Profile Answers by Nivetha Thinakaran Questions by Nivetha Thinakaran

• May 5th, 2015

In an autonomous transactions, we can have commit inside trigger.

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We have two type of constraints - Table Level and Column Level. Which is better and why..?

Mohit

• Oct 3rd, 2015

I think Table level contraints are imposed when we have to compare values in multiple columns,suppose delivery_date cannot be less than order_date..

abhilashnanupillai

 Profile Answers by abhilashnanupillai Questions by abhilashnanupillai

• Feb 20th, 2009

Constrains are the key word along with create table command. Different type of table constraints are primary key not null unique etc.

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How will you add additional conditions in SQL?

vikas patil

• Sep 25th, 2015

By using AND & OR

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PL/SQL declares a cursor implicitly for all SQL data manipulation statements, including quries that return only one row. However,queries that return more than one row you must declare an explicit cursor or use a cursor FOR loop.Explicit cursor is a cursor in which the cursor name is explicitly assigned to a SELECT statement via the CURSOR...IS statement. An implicit cursor is used for all SQL statements...

Manjunath

• Sep 1st, 2015

Hello, Given example PL/SQL program is comes under Implicit, Bcz 1. if its Explicit then cursor has to be declared in declarative part along with SELECT statement to retrieve the data from Database ...

Justo

• Jul 15th, 2015

Its an implicit cursor.

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Bharathiarun

• Aug 20th, 2015

Even if the Id is varchar, the rows are ordered by rownum.

Anand Prakash Joshi

• Aug 10th, 2015

Code
 

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How to retrieve odd and even number of rows from a table?

Sabbir

• Aug 17th, 2015

What programming language is this? Can you please provide this code in PHP ?

venkat

• Jun 27th, 2012

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union all

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S_NAME MARKS
ramu 60
ramu 40
ramu 50
karan 30
karan 96
karan 46

out put:
ramu "PASS"
karan "FAIL"

Elangovan

• Aug 13th, 2015

Code
 

Ritesh Kumar

• Mar 24th, 2015

"sql WITH t1 AS (SELECT name, COUNT ( result ) as tt_sub_pass FROM student WHERE result >= 40 group by name ...

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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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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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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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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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mktiwary  

 Profile Answers by mktiwary Questions by mktiwary

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

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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

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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?

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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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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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