On Jan 10, 2008 2:28 PM, David Giragosian <dgiragosian@xxxxxxxxx> wrote:
>
> On 1/10/08, Eric Butera <eric.butera@xxxxxxxxx> wrote:
> >
> > On Jan 10, 2008 2:02 PM, Philip Thompson <philthathril@xxxxxxxxx> wrote:
> > > On Jan 10, 2008, at 12:48 PM, Eric Butera wrote:
> > >
> > > > On Jan 10, 2008 1:33 PM, <reese@xxxxxxxxxxxxxxxx> wrote:
> > > >> I have been using define to create a constant for the link resource
> > > >> returned by mysql
> > > >> pconnect like so:
> > > >>
> > > >> $PL = @mysql_pconnect("localhost", $DBUser, $DBPass);
> > > >> define("SITE_DB",$PL);
> > > >>
> > > >>
> > > >> Later I use the constant to select my databases.
> > > >>
> > > >> mysql_select_db($SrcdbID ,SITE_DB);
> > > >>
> > > >> This code seems to be working as I expected and I have many
> > > >> thousands of llines of code
> > > >> done over several years using this construct.
> > > >>
> > > >> But, I happened to be reading the php doco today and noticed that
> > > >> you are not supposed to
> > > >> use define for resources, so question is, is what I am doing safe
> > > >> or am I going to run into
> > > >> problems and if so what is the best way to globally pass resources
> > > >> to multiple classes and
> > > >> functions, command line scripts etc?
> > > >>
> > > >>
> > > >> Cheers
> > > >> Charlie Reese
> > > >>
> > > >>
> > > > Hi Charlie!
> > > >
> > > > Well a CONSTANT is a value that doesn't change. I don't think that
> > > > makes sense for a DB connection. The connection command returns a
> > > > resource that could be different on each request depending on if
> > > > you've worked on different resources.
> > > >
> > > > You could just do this:
> > > > $GLOBALS['SITE_DB'] = @mysql_pconnect("localhost", $DBUser, $DBPass);
> > > >
> > > > Then inside your function reference it like this:
> > > > mysql_query($sql, $GLOBALS['SITE_DB']);
> > > >
> > > > This would be an easy mass find/replace that you could do. Global
> > > > variables are evil though.
> > > >
> > > > I personally use the registry pattern to hold an instance of the
> > > > database connection that can be lazy loaded whenever I need it. Then
> > > > inside of my gateway objects I pass that instance in the constructor
> > > > so they only have to know how to work with its interface. If you're
> > > > okay with using object that might be a nice road to travel. You could
> > > > also use the singleton pattern but I would advise against that because
> > > > what if you wanted 2 instances for different databases? I've never
> > > > ran across this myself but you never know. Plus it makes unit testing
> > > > a little tricky since you can't mock it as easily.
> > > >
> > > > Hopefully something in all this will help you to an answer.
> > >
> > >
> > > I don't agree that "Global variables are evil." If you have a valid
> > > purpose for defining a global variable, then go with it. The usual
> > > argument is that it could accidentally be changed elsewhere (and there
> > > are several more). However, defining a variable that you KNOW you're
> > > going to use only for a database connection, IMO, is perfectly fine.
> > >
> > > $GLOBALS['SITE_DB'] = @mysql_pconnect("localhost", $DBUser, $DBPass);
> > >
> > > If you accidently change $GLOBALS['SITE_DB'] elsewhere, then I think
> > > you have some bigger issues at hand. =P HTH.
> > >
> > > ~Philip
> > >
> > > "Personally, most of my web applications do not have to factor 13.7
> > > billion years of space drift in to the calculations, so PHP's rand
> > > function has been great for me..." ~S. Johnson
> > >
> > > --
> > >
> > > PHP General Mailing List (http://www.php.net/)
> > > To unsubscribe, visit: http://www.php.net/unsub.php
> > >
> > >
> >
> > Depending on what project I'm working on sometimes I use specific
> > globals on our older procedural code because:
> >
> > 1) It is our code
> > 2) It does not use outside code
> > 3) I'm the only developer working on it
> > 4) It is very simplistic
> >
> > By specific globals I mean that I have a "namespaced" entry such as
> > $GLOBALS['ericonly']['db'] and put things inside of ericonly. I
> > basically only use this for database connections and a few other very
> > specific things.
> >
> > Aside from that I'm not going to argue the merits of globals. Someone
> > else can do that as I've made up my mind and so have you. :)
> >
> > But just to prove that I'm right
> > http://www.google.com/search?hl=en&q=global+variables+are+evil&btnG=Search
> > :D
>
>
> Well...
>
> Personalized Results *1* - *10* of about *121,000* for
> *global<http://www.google.com/url?sa=X&oi=dict&ei=InGGR9TUIYO6gATv4ZHKBg&sig2=rv83RnqqLJDobfnA3d78Lg&q=http://www.answers.com/global%26r%3D67&usg=AFQjCNF3eQaMYwTOPeOFmY3o3_vKZoxD3g>
> variables<http://www.google.com/url?sa=X&oi=dict&ei=InGGR9TUIYO6gATv4ZHKBg&sig2=PtlnDj6B_ES74-UoJFdoYg&q=http://www.answers.com/variables%26r%3D67&usg=AFQjCNHUllfcxecDiCBZ124r8p5KyQoZlQ>are
> evil<http://www.google.com/url?sa=X&oi=dict&ei=InGGR9TUIYO6gATv4ZHKBg&sig2=QHGtFJrSLNf_0ARuYMWpHA&q=http://www.answers.com/evil%26r%3D67&usg=AFQjCNF5_Fag6ntgqNkFzuWVU9bEyb717Q>
> *. (*0.10* seconds)
>
> Personalized Results *1* - *10* of about *4,330,000* for
> *global<http://www.google.com/url?sa=X&oi=dict&ei=83CGR832BpbAggSao-G9Bg&sig2=b4uu-ZcrCZM0QWEXalxTNA&q=http://www.answers.com/global%26r%3D67&usg=AFQjCNH3VaZGgornyBLBavFsd_hljiBXsA>
> variables<http://www.google.com/url?sa=X&oi=dict&ei=83CGR832BpbAggSao-G9Bg&sig2=kto8MuCLr5saX5VPjN8ThQ&q=http://www.answers.com/variables%26r%3D67&usg=AFQjCNF1uZkzAKhsWmdBCI0IzFzgLSEAhA>are
> good<http://www.google.com/url?sa=X&oi=dict&ei=83CGR832BpbAggSao-G9Bg&sig2=ntLt-I0PIDJMXBMCk4OXCg&q=http://www.answers.com/good%26r%3D67&usg=AFQjCNHkthOJTyoPGlW9T2kzBpRwIqBc_A>
> *. (*0.25* seconds)
>
> Sorry, I couldn't resist. ;-)
>
> David
>
Nice try, but if you don't put your query in quotes "global variabels
are evil" then it is just finding searches that contain the words such
as the first result:
Global Variables Are Bad
A good example of a global variable is LoginId? (or NetworkId?)
whereby the app is making a lot of security or role-based calls and
must pass this all over ...
c2.com/cgi/wiki?GlobalVariablesAreBad - 24k -
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