U++ forum: Welcome to the forum

Search on this site

Search in forums

Home » U++ Library support » U++ SQL » SQL*, SQL&, SQL*:: ???

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

SQL*, SQL&, SQL*:: ??? [message #11297]

Sat, 01 September 2007 21:34

jeremyc
Messages: 4
Registered: August 2007

Junior Member

I do not understand all of these that I see in code. Can someone tell me the difference between:

SQL * Select(...);
SQL & Select(...);
SQL * ::Select(...);

I've seen it in example code all three ways. Maybe more.

Thanks,

Jeremy

Report message to a moderator

Re: SQL*, SQL&, SQL*:: ??? [message #11306 is a reply to message #11297]

Mon, 03 September 2007 00:14

mirek
Messages: 13975
Registered: November 2005

Ultimate Member

In 99% of cases, you use the first one.

"SQL &" throws an exception on error. Usually, with transactional RDBMS, using transaction block over exceptions is easier (even if not completely optimal), so it less often used.

"SQL * ::Select" is a bug, should be "SQL * UPP::Select", in what example you have spotted it? This has to be used in case when there is method named "Select" (name clash problem resolved by fully qualifying the name).

Mirek

Report message to a moderator

Re: SQL*, SQL&, SQL*:: ??? [message #19339 is a reply to message #11306]

Thu, 27 November 2008 19:21

sergeynikitin
Messages: 748
Registered: January 2008
Location: Moscow, Russia

Contributor

I have seen similar use in HomeBudget.
But there it was ::Update.

Incidentally, all want more examples on databases and SQL.

SergeyNikitin<U++>( linux, wine )
{
under( Ubuntu || Debian || Raspbian );
}

Report message to a moderator

Re: SQL*, SQL&, SQL*:: ??? [message #19341 is a reply to message #19339]

Thu, 27 November 2008 20:19

unodgs
Messages: 1366
Registered: November 2005
Location: Poland

Ultimate Contributor

sergeynikitin wrote on Thu, 27 November 2008 13:21

I have seen similar use in HomeBudget.
But there it was ::Update.

Incidentally, all want more examples on databases and SQL.

:: Is not necessary, it is even wrong as all upp functions belogns to Upp namespace.
I often had in my apps Update method in which I had SQL * ::Update. Without scope selector I would have names conflict. I still use :: instead of UPP:: because it's shorter.

Report message to a moderator

Re: SQL*, SQL&, SQL*:: ??? [message #19342 is a reply to message #19341]

Thu, 27 November 2008 20:24

unodgs
Messages: 1366
Registered: November 2005
Location: Poland

Ultimate Contributor

operator * calls Execute(), & calls ExecuteX which throws SqlExc if something is wrong. Useful if you do some operation in a transaction.

[Updated on: Thu, 27 November 2008 20:24]

Report message to a moderator

Previous Topic:	Syntactic sugar
Next Topic:	MSSQL new strange story :)

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Mon Apr 29 02:01:43 CEST 2024

Total time taken to generate the page: 0.05019 seconds