During my 8 years of career, I have been involved in many interviews. Quite often, I act as the interview. If I am the interviewer, I ask many questions – from easy questions to difficult ones. When I am the interviewee, I frequently get an opportunity to ask the interviewer some questions back. Regardless of the my capacity in attending the interview, I always make it a point to ask the interviewer at least one question. Let’s learn how to fix Error 8117.
SQL SERVER – Solution Part 2 – A Quick Puzzle on SQL JOIN and NULL – SQL Brain Teaser
Some questions are timeless and they never grow old; no matter how much they grow old their interest never dies. Earlier, I asked a simple puzzle based on a conversation on SQLAuthority Page, and have received an overwhelming response from readers. I still get emails related to this puzzle every day. Let us see a quick puzzle between SQL Join and SQL Null.
SQL SERVER – Puzzle Involving NULL – Resolve – Error – Operand data type void type is invalid for sum operator
Today is Monday let us start this week with interesting puzzle. Yesterday I had also posted quick question here: SQL SERVER – T-SQL Scripts to Find Maximum between Two Numbers
SQL SERVER – Explanation and Understanding NOT NULL Constraint
NOT NULL is integrity CONSTRAINT. It does not allow creating of the row where column contains NULL value. Most discussed question about NULL is what is NULL? I will not go in depth analysis it. Simply put NULL is unknown or missing data. When NULL is present in database columns,…
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SQL SERVER – Explanation and Comparison of NULLIF and ISNULL
Explanation of NULLIF
Syntax:
NULLIF ( expression , expression )
Returns a null value if the two specified expressions are equal. NULLIF returns the first expression if the two expressions are not equal. If the expressions are equal, NULLIF returns a null value of the type of the first expression. NULLIF is equivalent to a searched CASE function in which the two expressions are equal and the resulting expression is NULL.
SQL SERVER – LEN and DATALENGTH of NULL Simple Example
Simple but interesting – In recent survey I found that many developers making this generic mistake. I have seen following code in periodic code review. (The code below is not actual code, it is simple sample code) DECLARE @MyVar VARCHAR(10) SET @MyVar = NULL IF (LEN(@MyVar) = 0) … I…
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