Difference between exists and in operators in oracle?

what is difference between exists and in operators in oracle?
what is faster and why?

Malli wrote:
what is difference between exists and in operators in oracle?
what is faster and why?Is this a homework question?
Have you done any tests yourself to see which is faster?

Similar Messages

What is the difference between exists and in

hi all
if i have these queries
1- select ename from emp where ename in ( select ename from emp where empno=10)
and
2- select ename from emp where exists ( select ename from emp where empno=10)
what is the difference between exists and in is that only when i use in i have to bring the field name or what.... i mean in a complex SQL queries is it will give the same answer
Thanks

You get two entirely different result sets that may be the same. Haah! What do I mean by that.
SQL> select table_name from user_tables;
TABLE_NAME
BAR
FOO
2 rows selected.
SQL> select table_name from user_tables where table_name in (select table_name from user_tables where table_name = 'FOO');
TABLE_NAME
FOO
1 row selected.
SQL> select table_name from user_tables where exists(select table_name from user_tables where table_name = 'FOO');
TABLE_NAME
BAR
FOO
2 rows selected.So, why is this? the WHERE EXISTS means 'if the next is true', much like where 1=1 being always true and 1=2 being always false. In this case, where exists could be TRUE or FALSE, depending on the subquery.
WHERE EXISTS can be useful for something like testing if we have data, without actually having to return columns.
So, if you want to see if an employee exists you might say
SELECT 1 FROM DUAL WHERE EXISTS( select * from emp where empid = 10);
If there is a row in emp for empid=10, then you get back 1 from dual;
This is what I call an 'optimistic' lookup because the WHERE EXISTS ends as soon as there is a hit. It does not care how many - only that at least one exists. It is optimistic because it will continue processing the table lookup until either it hits or reaches the end of the table - for a non-indexed query.

Difference between exists and createIf

Hi all,
In Node functions we are having createIf and exists. what is the difference between createIf and exists? Where we have to use createIf and where we have to use exists?
Thanks
Sridhar

Hi Sridhar
Source Node --- Exists ---target Node ..... this says that the target node will be created if and only if the source node (may be source occurences is 0...1)through which you are mapping exists or not.. If it than target node will be created if not than it wont be created ...
Source node -
creatIf---target Node ...... this says that there will be some condition in source side ...if that condition is true than create the target node otherwise do not create
Regard
Abhi

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Hello,
While creating an organization, when do we use Internal and External? Basically whats the difference between these two options in the Work Structure screen while defining organizations?
Thank You
Kumar

Hello,
Just to add on information.
Internal organizations are such as departments, divisions, and sections
External organizations are such as benefits carriers, tax authorities, and recruiting agencies.Organization classification Payee Organization when defining an external organization that is the recipient of a third party payment from an employee, for example a court-ordered payment. You can then select this organization on the Personal Payment Method window when entering a third party payment method.
Generally we do not tag employees(Organization classification HR Organization) to external organizations.
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Difference between ANY and ALL operators

I am learning the basics of ANY and ALL operators.
Retrieving all employees in Dept 30 whose sal is greater than ANY employees in Dept 20
SQL> SELECT * FROM EMP;
     EMPNO ENAME           JOB              MGR HIREDATE         SAL       COMM     DEPTNO
      7369 SMITH           CLERK           7902 17-DEC-80        800                    20
      7499 ALLEN           SALESMAN        7698 20-FEB-81       1600        300         30
      7521 WARD            SALESMAN        7698 22-FEB-81       1250        500         30
      7566 JONES           MANAGER         7839 02-APR-81       2975                    20
      7654 MARTIN          SALESMAN        7698 28-SEP-81       1250       1400         30
      7698 BLAKE           MANAGER         7839 01-MAY-81       2850                    30
      7782 CLARK           MANAGER         7839 09-JUN-81       2450                    10
      7788 SCOTT           ANALYST         7566 19-APR-87       3000                    20
      7839 KING            PRESIDENT            17-NOV-81       5000                    10
      7844 TURNER          SALESMAN        7698 08-SEP-81       1500          0         30
      7876 ADAMS           CLERK           7788 23-MAY-87       1100                    20
     EMPNO ENAME           JOB              MGR HIREDATE         SAL       COMM     DEPTNO
      7900 JAMES           CLERK           7698 03-DEC-81        950                    30
      7902 FORD            ANALYST         7566 03-DEC-81       3000                    20
      7934 MILLER          CLERK           7782 23-JAN-82       1300                    10
14 rows selected.
SQL> SELECT * FROM EMP WHERE DEPTNO=20;
     EMPNO ENAME           JOB              MGR HIREDATE         SAL       COMM     DEPTNO
      7369 SMITH           CLERK           7902 17-DEC-80        800                    20
      7566 JONES           MANAGER         7839 02-APR-81       2975                    20
      7788 SCOTT           ANALYST         7566 19-APR-87       3000                    20
      7876 ADAMS           CLERK           7788 23-MAY-87       1100                    20
      7902 FORD            ANALYST         7566 03-DEC-81       3000                    20
SQL> SELECT * FROM EMP WHERE DEPTNO=30;
     EMPNO ENAME           JOB              MGR HIREDATE         SAL       COMM     DEPTNO
      7499 ALLEN           SALESMAN        7698 20-FEB-81       1600        300         30
      7521 WARD            SALESMAN        7698 22-FEB-81       1250        500         30
      7654 MARTIN          SALESMAN        7698 28-SEP-81       1250       1400         30
      7698 BLAKE           MANAGER         7839 01-MAY-81       2850                    30
      7844 TURNER          SALESMAN        7698 08-SEP-81       1500          0         30
      7900 JAMES           CLERK           7698 03-DEC-81        950                    30
6 rows selected.
SQL> SELECT * FROM EMP
2 WHERE SAL>ALL
3 (SELECT SAL FROM
4 EMP WHERE DEPTNO=20)
5 AND DEPTNO=30;
no rows selected
SQL> SELECT * FROM EMP
2   WHERE SAL>ANY
3   (SELECT SAL FROM
4   EMP WHERE DEPTNO=20)
5   AND DEPTNO=30;
     EMPNO ENAME           JOB              MGR HIREDATE         SAL       COMM     DEPTNO
      7698 BLAKE           MANAGER         7839 01-MAY-81       2850                    30
      7499 ALLEN           SALESMAN        7698 20-FEB-81       1600        300         30
      7844 TURNER          SALESMAN        7698 08-SEP-81       1500          0         30
      7521 WARD            SALESMAN        7698 22-FEB-81       1250        500         30
      7654 MARTIN          SALESMAN        7698 28-SEP-81       1250       1400         30
      7900 JAMES           CLERK           7698 03-DEC-81        950                    30
6 rows selected.From a book by Damir Bersinic:
An easy shorthand enables you to remember the distinction between ANY and
ALL. If a query condition is >ANY, each row in the result set is greater than the lowest value returned. When a query is >ALL, each row in the result set is greater than the highest value returned.
He meant ; If a query condition is >ANY, each row in the result set is greater than the lowest value returned by the subquery. Didn't he?
I couldn't find ANY and ALL operators in 10g SQL Reference? Are these operators being replaced by anything?
Message was edited by:
for_good_reason

Look this
>ANY------- means more than minimum
Ex: sql> select empno,ename,job from emp
where sal>ANY(select sal from emp job='CLERK');
w/o using >ANY the query will be
sql>select empno,ename,job from emp
where sal>(select min(sal) from emp job='CLERK');
>ALL-------- means more than the maximum
Ex: sql> select empno,ename, job sal from emp
where sal> ALL(select Avg(sal) from emp Group by deptno);
w/o using >ALL the query will be
sql> select empno,ename, job sal from emp
where sal> (select max(Avg(sal)) from emp Group by deptno);
sandeep

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Difference between in and exist?

difference between in and exist?

Note the name of this forum is "SQL Developer *(Not for general SQL/PLSQL questions)*", so only for issues with the SQL Developer tool. As AlexAnd suggested, please post these questions under the dedicated [SQL And PL/SQL|https://forums.oracle.com/forums/forum.jspa?forumID=75] forum.
Regards,
K.

Can Oracle be forced to use the spatial index for sdo_filter in combination with an or clause? Difference between Enterprise and SE?

We’re seeing the following issue: sql - Can Oracle be forced to use the spatial index for sdo_filter in combination with an or clause? - Stack Overflow (posted by a colleague of mine) and are curious to know if this behaviour is due to a difference between standard and enterprise, or could we doing something else wrong in our DB config.?
We have also reproduced the issue on the following stacks:
Oracle SE One 11.2.0.3 (with Spatial enabled)
Redhat Linux 2.6.32-358.6.2.el6.x86_64 #1 SMP Thu May 16 20:59:36 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
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BTW: when asking questions about queries here, it would be nice if you posted the queries here as well, so that we do not have to check another website in order to see what you are doing. Plus it will probably get you more answers, because not everyone can be bothered to click on that link. It would also have been nice if you had posted your own answer on the other post here as well, because my recommendation would have been to use union all - but since you already found that out for yourself my recommendation would have been a little late.

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please give the comments

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Others think upgrade when new version replace database in place, and migration when new version include a move of database. 
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Well, after these explanations, your upgrade/migratation notion will not be more clear, but I think that is not very important, only a terminology game. The most important is to know what you need : new version or new release. 
 
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Kindly share the Knowledge.
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Srini_Chavali wrote:
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MOS Doc 1302189.1
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Thank in advance.
I want to know Difference between 'setup' and 'configuration'(Oracle Apps ). Could you provide the details with an example, please?
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Raghavendra Rao

Business Requirement:-
===============
A company may want to allow all of its employees to make purchases up to $10 without having such purchases approved. Another company may have a business rule that each employee’s approval limit depends on his or her position within the organization.
Question:-
=======
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Hello,
This is not purely oracle question; but in documentation so many times we find 2 terms:
A. Logical
B.Virtual.
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Girish,
I wont say that I am correcting you as this is like that half glass full/empty thing.May be what I see is half empty , you would see the same as half full.
Well now coming to the explanation.I am saying honestly , I got more confused after reading your definitions.What do you mean by saing that tablespace is not virtual.I see it as purely virtual.We don't say it as virtual tablespace or logical tablespace but it is actualy logical/virtual, having no existance but just the definition right?
How can you say that the size of virtual is larger than logcial?The size of tablespace is actualy the sum total of size of datafiles.So it actualy becomes very larger right?Much larger than JVM which is of few megs only.
The point 3 totally knocked me out.I have no idea what you said.
Ok I tell you this.Just remember the definition that Hans gave already.If you ask me than its the best definition that we can have. Just remember this and if some one asks you more further than give them your point 3 definition and tell them understand this ;-).Please don'tmind I am just kidding. Its just semantics.Don't get lost into it.You will find many people using both the terms interchangibly. So its ok.I shall stick with Hans's defintion,simple and concise.There are lot more other topics to dig upon in oracle.I can mail you lots of them.Spend time on those.Don't think that I am demotivating you.I understand you asked only because you have a doubt.But we got a good resolution of it and beyond that, its not of much use to dig it atleast not in the technial terms.
Cheers
Aman....
PS:Are you on oraclecommunity.net?

Difference between exists and in operators in oracle?

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