What is correlated sub-query?

7 Answers   Oracle,

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what is the command used to fetch first 5 characters of the string? : Sql dba

0 Answers  

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What is a unique key and primary key and foreign key?

0 Answers  

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What is the unique index?

0 Answers  

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What are the types of index in sql?

0 Answers  

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which tcp/ip port does sql server run on? : Sql dba

0 Answers  

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How do you rank data in sql?

0 Answers  

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write a query to remove null following table are id name 101 dinesh null jyothi null bharathi 102 suresh null shilpha 103 prakesh null suma i want the output format like id name 101 dinesh 102 suresh 103 prakesh

3 Answers   TCS,

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how to check the 3rd max salary from an employee table? One of the queries used is as follows: select sal from emp a where 3=(select count(distinct(sal)) from emp b where a.sal<=b.sal). Here in the sub query "select count(distinct(sal)) from emp b where a.sal<=b.sal" or "select count(distinct(sal)) from emp b where a.sal=b.sal" should reveal the same number of rows is in't it? Can any one here please explain me how is this query working perfectly. However, there is another query to get the 3rd highest of salaries of employees that logic I can understand. Pls find the query below. "select min(salary) from emp where salary in(select distinct top 3 salary from emp order by salary desc)" Please explain me how "select sal from emp a where 3=(select count(distinct(sal)) from emp b where a.sal<=b.sal)" works source:http://www.allinterview.com/showanswers/33264.html. Thanks in advance Regards, Karthik.

4 Answers  

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what is the difference between a local and a global temporary table? : Sql dba

0 Answers  

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what is self join and why is it required? : Sql dba

1 Answers  

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How delete all records from table in sql?

0 Answers  

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