is there any difference between != and <>

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is there any difference between != and <>

karthik M

One Orange Chip

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November 7, 2007 at 1:22 am

#126432

Pls tell me
karthik

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Peter Gadsby SSCrazy Points: 2718 More actions · Answer 1

I think they are the same

Pete

Peter Gadsby
Business Intelligence Consultant
www.hgconsult.co.uk

Mayank Khatri SSCertifiable Points: 7984 More actions · Answer 2

A) <>

B) !=

Both mean NOT EQUAL TO but (B) is not SQL 92 standard (The third version of SQL Server)

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 3

I agree with Mayank... just to add to that, the != will actually appear in execution plans as <>. Sounds strange, but I can always tell who wrote the code if != is used... some Java programmer 😉

The reason I really don't like it is because 1) it's not what I'm accustomed to for identifying an inequality (used to <> because of Math) and 2) for some reason, it's hard for me to see when I'm reviewing code... I guess I just don't think there should be an = sign in an inequality 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 4

Jeff Moden (11/7/2007)
Sounds strange, but I can always tell who wrote the code if != is used... some Java programmer 😉

😀 I always use !=, but I'm not a Java programmer. An old habit from my C background... 😉

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 5

Heh... I was going to include "C" programmers in that mix :D, but wasn't sure it was true and I work mostly with Java programmers to boot.

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Shaun McGuile SSCarpal Tunnel Points: 4141 More actions · Answer 6

!= is th inequality in C# get used to it as CLR programming takes off!:hehe:

Hiding under a desk from SSIS Implemenation Work :crazy:

Vincent Chute Newbie Points: 7 More actions · Answer 7

Jeff Moden (11/7/2007)The reason I really don't like it is because 1) it's not what I'm accustomed to for identifying an inequality (used to <> because of Math) and 2) for some reason, it's hard for me to see when I'm reviewing code... I guess I just don't think there should be an = sign in an inequality 😉

The exact opposite for me.

I learnt != in maths so seeing <> has always been a wtf moment for me.

Just different notation dialects.

"!" being a shorthand for the logical NOT operator means != is almost instinctive for me.

Similarly I use "~" as shorthand for approx* whenever I am writing notes for myself.

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 8

Shaun McGuile (11/9/2007)
!= is th inequality in C# get used to it as CLR programming takes off!:hehe:

Heh... good point. But have had this argument with many other folks... there's very little you will ever need a CLR for if you actually know T-SQL well 😉 CLR's are for "C" programmers that don't 😛

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 9

Vincent Chute (11/9/2007)
The exact opposite for me.
I learnt != in maths so seeing <> has always been a wtf moment for me.
Just different notation dialects.
"!" being a shorthand for the logical NOT operator means != is almost instinctive for me.
Similarly I use "~" as shorthand for approx* whenever I am writing notes for myself.

Perfect answer... "Just different notation dialects"...

Now, using the Tilde to represent approximation is something that I agree with!

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Michael Valentine Jones SSC Guru Points: 64818 More actions · Answer 10

These all give me the same query plan:

select * from authors where au_id <> '172-32-1176'

select * from authors where au_id != '172-32-1176'

select * from authors where not au_id = '172-32-1176'

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 11

Heh... also notice that the != gets converted to a <> in the query plan output 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 12

Jeff Moden (11/9/2007)
Heh... good point. But have had this argument with many other folks... there's very little you will ever need a CLR for if you actually know T-SQL well 😉 CLR's are for "C" programmers that don't 😛

I'll disagree with you on that point. There's a lot of things that the CLR is better at than T-SQL. String manipulation, complex mathematical calculations, external calls (web service). All far easier and far faster from CLR functions/procs

Whether or not those belong in the DB in the first place is a different argument. 🙂

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

Jeff Moden SSC Guru Points: 1004365 More actions · Answer 13

Sting manipulation? Complex mathematical calcs? Heh... Let's have a race... let's start with string manipulation... How about splitting a comma seperated column and returning a table with the PK of each row and the split value... 1 row for every split on a 100k row table? You write a CLR to solve, I'll write the T-SQL to solve. I'll even be happy to provide the test data if you want.

Or, how about doing Init Caps on a column in a million row table?

Or, how about removing all characters except digits and letters from a column in a million row table?

Or, name the problem...

...and here's your advantage... I don't have 2k5 to play with... I have to do it using only T-SQL 'cause I only have 2k. 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Shaun McGuile SSCarpal Tunnel Points: 4141 More actions · Answer 14

Jeff you rascal 😀

Hiding under a desk from SSIS Implemenation Work :crazy: