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From: David McGlone on 28 Jun 2010 10:29 On Sunday 27 June 2010 22:12:41 Brandon Rampersad wrote: > no At least smack me and give us an explanation. :-) -- Blessings, David M.
From: Andrew Ballard on 28 Jun 2010 11:14 On Mon, Jun 28, 2010 at 10:27 AM, David McGlone <david(a)dmcentral.net> wrote: > Tanel, we both learned something. I didn't fully understand join myself yet, > but I think I do now. > > but let me ask this if the join wasn't there would an if statement like I > mentioned have worked? > > Blessings, > David M. I think you are confusing a few things. You can't really rely on testing "empty(DB_HIDDENPANELS)" because the value of the constant DB_HIDDENPANELS is most likely a string that was set with an earlier call to define. The OP could have tested for the column value "hiddenpanel" using an if (...) test as you suggeted. However, given that the OP stated he "would like to select hiddenpanel only if there is a corresponding value in DB_HIDDENPANELS," the INNER JOIN will do that at the database query level, so an if (...) then test in PHP isn't really necessary. Andrew
From: David McGlone on 28 Jun 2010 11:47
On Monday 28 June 2010 11:14:53 Andrew Ballard wrote: > On Mon, Jun 28, 2010 at 10:27 AM, David McGlone <david(a)dmcentral.net> wrote: > > Tanel, we both learned something. I didn't fully understand join myself > > yet, but I think I do now. > > > > but let me ask this if the join wasn't there would an if statement like I > > mentioned have worked? > > > > Blessings, > > David M. > > I think you are confusing a few things. You can't really rely on > testing "empty(DB_HIDDENPANELS)" because the value of the constant > DB_HIDDENPANELS is most likely a string that was set with an earlier > call to define. The OP could have tested for the column value > "hiddenpanel" using an if (...) test as you suggeted. However, given > that the OP stated he "would like to select hiddenpanel only if there > is a corresponding value in DB_HIDDENPANELS," the INNER JOIN will do > that at the database query level, so an if (...) then test in PHP > isn't really necessary. That is exactly what I was wondering. I haven't got to joins yet, and didn't understand them at all until Richard explained a few minutes ago. I knew my suggestion was a complete shot in the dark and I did feel stupid posting it, but I'm glad now, because I learned something invaluable. Thanks to this list, someday, which I hope is sooner than later, I'll be able to help somebody with complete confidence. -- Blessings, David M. |