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Interview Questions
Through this article, we are going to discuss three important interview questions of SQL which are given below:- 1) Can we create clustered index on a column containing duplicate values? 2) Can we create a Primary Key on a table on which a clustered index is already defined? 3) If a clustered index is already defined on a […]
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Question of the Month Suppose we have a table emp_plan which contains 4 columns “Empid” (employeeid), Planid (Projectid), Startdate(Allocation Start date) and Enddate (Allocation Enddate). Its structure is given below:-4 Create table emp_plan (empid nvarchar(200),planid nvarchar(20),startdate datetime, enddate datetime) Also below is the script to enter sample data into the table:- insert into emp_plan(empid,planid,startdate,enddate) select ‘001’,’planA’,’2015-05-15′,’2015-05-30′ […]
Continue ReadingComplete months between two given dates Below script will help in finding the complete months within the 2 given dates. In the below script we takes below dates as exampleStartdate =2015-07-05 Enddate =2016-01-06 /**********************Script Start**************************/ IF (object_id(‘tempdb..#month’) is not null) DROP TABLE #month CREATE TABLE #month (id int identity(1,1),MonthStartDate DATETIME,MonthEndDate DATETIME) DECLARE @startdate AS DATETIME […]
Continue ReadingComplete weeks within two given dates Sometimes we need to find out the complete weeks within two given dates. Below script will help in finding the complete weeks within 2 given dates. In this script, I have used below dates as exampleStartdate=2015-04-12 Enddate=2015-06-10 SET DATEFORMAT YMD if (object_id(‘tempdb..#weekdays’) is not null) drop table #weekdays Declare […]
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Technical Round Database Interview Questions 1) What are the different types of Trace flags which we used for detecting the Deadlock? 2) What are the different types of database backups? 3) How do you perform the Error handling in SQL Server? 4) What is the ACID property in SQL Server? 5) What are the best […]
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SQLTea – Our new SQL Tutorial App on Google Play Store We are happy to announce our new SQL tutorial app SQLTea ( Native android app) for SQL learning which includes articles from this blog. This application includes 1) Articles for basic concepts like Normalization, Constrains, Joins, SQL Functions, SQL commands etc and also advance […]
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Suppose we need to find out the name of all the months in a given year (Year will be given as an input parameter) where first day of the month falls on weekend (Saturday or Sunday). So what should be the query/stored procedure to get the above result?
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Question:- How many NULL value allowed in a column in which Unique constraint is defined in SQL Server? Options:- a) 1 b) 2 c) More than 1 Answer :- Option a) 1 In SQL Server, we can Insert only one null value in a column where we have defined the Unique Constraint. For Example , suppose […]
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Question:- Suppose there are two tables A and B and we need to write 3 SQL queries which returns the record set as shown in the below figure. First Query:- In this case, you have to write a SQL Query using SQL JOIN which return the data which is not common to these two tables A& B as shown in […]
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Question :- In which database temporary tables are created in SQL Server? 1) User database (where temporary table are defined) 2) Master database 3) TempDB (Correct Answer) 4) Model Database 5) None of the above Answer Thanks to all who attempted this question. 84% people gives the correct answer:-) Correct answer […]
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