Cast vs. Convert

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Cast vs. Convert

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Tom Garth SSCertifiable Points: 6193 More actions · Answer 1

I thought I knew the answer, but BZZZZZZT!

Nice question.

Tom Garth
Vertical Solutions[/url]

"There are three kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." -- Will Rogers

Erwin Oosterhoorn SSCrazy Points: 2289 More actions · Answer 2

bouarroudj Mohamed (3/8/2010)
CONVERT works across all platforms & has more capabilities in SQL Server is also true

That is what I am looking at as well, does this not mean the same as the given right answer?

If one has less the other must have more?

KevinC. SSCommitted Points: 1570 More actions · Answer 3

erwin.oosterhoorn (3/8/2010)
bouarroudj Mohamed (3/8/2010)
CONVERT works across all platforms & has more capabilities in SQL Server is also true
That is what I am looking at as well, does this not mean the same as the given right answer?
If one has less the other must have more?

If I understand correctly, CONVERT is MS SQL specific whereas CAST is ANSI-SQL and will work on multiple platforms (i.e. Oracle, DB2, etc.).

Therefore, the above statement is incorrect because CONVERT does NOT work across all platforms (though it does have more capabilities in SQL Server).

Please correct me if I'm wrong. 😀

--

Kevin C.

Erwin Oosterhoorn SSCrazy Points: 2289 More actions · Answer 4

KevinC. (3/8/2010)
erwin.oosterhoorn (3/8/2010)
bouarroudj Mohamed (3/8/2010)
CONVERT works across all platforms & has more capabilities in SQL Server is also true
That is what I am looking at as well, does this not mean the same as the given right answer?
If one has less the other must have more?
If I understand correctly, CONVERT is MS SQL specific whereas CAST is ANSI-SQL and will work on multiple platforms (i.e. Oracle, DB2, etc.).
Therefore, the above statement is incorrect because CONVERT does NOT work across all platforms (though it does have more capabilities in SQL Server).
Please correct me if I'm wrong. 😀
--
Kevin C.

Thanks Kevin, if you are correct than that makes sense now.

Rune Bivrin SSCrazy Eights Points: 8440 More actions · Answer 5

sknox (3/8/2010)
Rune Bivrin (3/8/2010)
Good question, but which alternative is correct depends on how you define platform. If you define "platform" as "versions of SQL Server", then CONVERT works in every version whereas CAST was introduced in 7.0 (IIRC - could've been 2000).
Well, if you define "black" as "white", you can prove anything. The standard definition of platform is independent of versions of specific platforms. I think it's quite ironic that you're criticizing a question that compares an ANSI standard function to a vendor-specific function by relying on a non-standard definition.

Who says I'm criticizing the question?

I'm merely pointing out that since this is SQL Server Central, and not DBMS central, such an interpretation isn't completely out of order. And from that point of view CONVERT is somewhat more universal, even if I sincerely hope noone still wrestles with SQL Server 6.5...

Just because you're right doesn't mean everybody else is wrong.

Joe SQL SSChasing Mays Points: 620 More actions · Answer 6

I figured the answer was going to be something related to CONVERT having the style parameter (and hence more capabilities), but then saw in BOL (2005) that "CAST and CONVERT provide similar functionality" so chose the last answer.. doh! Should have gone with gut feeling but have been tricked too many times from previous questions which always give the BOL answer as the correct one (even if it isn't). Although I see now that BOL for 2008 does not have that statement in it.

Just can't win....

vk-kirov SSCertifiable Points: 7686 More actions · Answer 7

erwin.oosterhoorn (3/8/2010)
bouarroudj Mohamed (3/8/2010)
CONVERT works across all platforms & has more capabilities in SQL Server is also true
That is what I am looking at as well, does this not mean the same as the given right answer?
If one has less the other must have more?

I agree with this. The phrasing of the answers seems quite ambiguous to me.

"CAST ... has less capabilities in SQL Server" – according to what? According to "CAST in another RDBMS", according to "CAST in SQL-92", or according to "CONVERT in MSSQL/another RDBMS"?

KevinC. (3/8/2010)
If I understand correctly, CONVERT is MS SQL specific whereas CAST is ANSI-SQL and will work on multiple platforms (i.e. Oracle, DB2, etc.).
Therefore, the above statement is incorrect because CONVERT does NOT work across all platforms (though it does have more capabilities in SQL Server).
Please correct me if I'm wrong. 😀

CONVERT is not MSSQL specific, it also works on Sybase ASA/ASE.

Also CONVERT exists in SQL-92, but has different meaning (see below).

I had checked documentation on several RDBMS platforms (MSSQL, Sybase, Oracle, DB2, PostgreSQL, MySQL) before I answered the question, here is the result:

– CAST works across all these platforms, and may have additional MULTISET parameter in Oracle;

– CONVERT works across all platforms, but has two different meanings. In MSSQL/Sybase it converts data from one type to another, in other databases it converts text data from one encoding to another (therefore working like COLLATE clause in MSSQL), as described in SQL-92.

Also I found an issue in the QOD explanation:

agrawal.prakriti
CAST is the more ANSI-standard of the two functions, meaning that while it's more portable

This sentence is somewhat incomplete, isn't it? (although I'm a total noob at English language 🙂 )

TravisDBA SSCoach Points: 15780 More actions · Answer 8

bouarroudj Mohamed (3/8/2010)
CONVERT works across all platforms & has more capabilities in SQL Server is also true

My thinking exactly and that was my answer too, which I got wrong. Question was a little confusing and nebulous..

"Technology is a weird thing. It brings you great gifts with one hand, and it stabs you in the back with the other. ...:-D"

Paul White SSC Guru Points: 150467 More actions · Answer 9

Can anyone else hear that high-pitched whining sound in here? 😛 😉 😀

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

vk-kirov SSCertifiable Points: 7686 More actions · Answer 10

sknox (3/8/2010)
I'm quite surprised that, at the time I answered the question, approximately 3/4 of people got this question wrong.

Do you think this is because lack of knowledge? I think many people answered "incorrect" because of the phrasing.

TomThomson SSC Guru Points: 104773 More actions · Answer 11

Paul White (3/9/2010)
Can anyone else hear that high-pitched whining sound in here? 😛 😉 😀

Yes, I hear it loud and clear. Pitiful :crying:, ain't it?:-D ;-). And just a little nauseating :sick: :laugh:.

Tom

jmatayoshi SSCommitted Points: 1649 More actions · Answer 12

this question is ambiguous, both answers 2 and 4 are almost the same

Tom Garth SSCertifiable Points: 6193 More actions · Answer 13

jmatayoshi (3/11/2010)
this question is ambiguous, both answers 2 and 4 are almost the same

So Almost the Same = Ambiguous?

What if they were Somewhat Different? Would that be better?

Tom Garth
Vertical Solutions[/url]

"There are three kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." -- Will Rogers

Paul White SSC Guru Points: 150467 More actions · Answer 14

jmatayoshi (3/11/2010)
both answers 2 and 4 are almost the same

That statement makes my head spin.

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

SQLRNNR SSC Guru Points: 281334 More actions · Answer 15

Paul White (3/12/2010)
jmatayoshi (3/11/2010)
both answers 2 and 4 are almost the same
That statement makes my head spin.

Hah - Paulpatine spinning like the MCP before Tron obliterates it with the disk - oh yeah.

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
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