Interview Question - How to generate values from 1 to 1000 ? without using .....

This question comes across as a straight forward question but can prove lethal to gauge the turnaround time. It also checks the ability of the person to reach the destination when virtually all the doors are closed.

Well the complete question is

" How to generate values from 1 to 1000 without using WHILE loop and Cursor ? and Using single SELECT or block of code"

The question became interesting with the last part because most of us would have thought about using loop/cursor but that is forbidden.. and we also have to use single SELECT or block of code .. 

Okay.. What does that mean ? Is it some kind of a clue to answer this question ? 

MS-CRM - Query to list the TimeZones for the Active Users

In MS-CRM database as we know end user can set the timezone of his choice for himself / herself. And after that all the data that end user sees on CRM UI would be displayed in the timezone that he/she has opted for. 

Now, the question is where does CRM stores the TIMEZONE related information? hence comes the TimeZoneDefinitionBase table to rescue. 

It holds the info such as 

• TimeZoneCode - Unique Integer value representing each timezone
• UserInterfaceName - Displays info in-terms of UTC +/- Hrs
• StatndardName - Gives away the global standard name for the TimeZone that everyone can understand

Interview Question - What will be output for the query ?

Today's question deal with somewhat neglected part of the SQL server. I say Neglected because it is very rarely used.

What will be the output for the following query 

DECLARE @TEST TABLE
(
COL1 SMALLINT,
COL2 SMALLINT
)


INSERT INTO @TEST
SELECT 13,76

SELECT 
COL1 & COL2  AS [&]
,COL1 | COL2 as [|]
,COL1 ^ COL2 AS [^]
,~COL1 AS [~]
,~COL2 AS [~2]
,~ COL1 | COL2 & COL1 ^ COL2 AS Precedence
FROM @TEST

Tip - IN clause other way around

How to do you write a query to fetch the records from a table where particular value is present in 2 different columns or in either of them ? 

Phewww.. pretty simple isn't it ?

Let us give it a shot...

DECLARE @TAB TABLE
(
ID SMALLINT,
NUM SMALLINT
)

INSERT INTO @TAB
SELECT 1,1 UNION ALL
SELECT 2,1 UNION ALL
SELECT 3,3 UNION ALL
SELECT 1,4

With reference to the question raised @ the top we have to write a query to find the records containing 1 in either of the columns from @TAB or featuring in both of them.. 

Interview Question - What is the difference between Table Variable and Temp Table ?

Few days back, one of my colleague asked me about the difference between Table variable and Temp table. Although I did manage to tell him few difference that got him going but that answer did not satisfy me. So to settle the nerve I ended up reading about them and got to know few more differences between table variable and temp table. 

Then it occurred to me that it's good candidate for the blog entry as this question fielded quite often during screening process. 

Below given screenshot shows the difference between the Table variable and Temp table

NULL with NOT IN () caluse

Most of you must be aware of the fact that NULL value causes more problem than anything else database world. Well here is an example which may or already have ruined few minutes @m some point in your career.

NULL means nothing then Why on the earth should we care about it ? well it is one of the most important thing that DB developer should care or you'd be doomed for unexpected results.

Let's see one example of NULL causing few of us headache..