SQL Interview Questions

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Join results of T1 and T2 : T1 1 2 3 NULL  T2 1 4 NULL
 
SQL Query to Find All Employees Who Are Also Managers
 
 
SQL Query to Find All Employees Who Are not
a Managers
 
How to find Nth highest salary from a table
 
Query to return only duplicate records
 
How will you delete duplicate records
 
Show string value coming between 2 dots. like
input : hello.welcome.bye
output : welcome
 
input:
SubjectID       StudentName
----------      -------------
1               Mary
1               John
1               Sam
2               Alaina
2               Edward
output:
SubjectID       StudentName
----------      -------------
1               Mary, John, Sam
2               Alaina, Edward  
x

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