Re: Select from multiple tables

Dear Kranthi

You have to be clear what you decide especially when you are getting
multiple rows. To get just a single row you can use LIMIT clause.

But it would return only one row. Now you  have to decide which row.

So i think you decide on what you require and see how can you uniquely
identify that row
============
regds
amit

"The difference between fiction and reality? Fiction has to make sense."


On Thu, Mar 1, 2012 at 9:45 AM, Kranthi Krishna <[email protected]>wrote:

> Hi,
>
> The examples I saw were regarding cartesian join not inner join.  I
> will read about inner joins. Also, the example i mentioned seems to be
> a mistake. Both school and type will not be similar at the same time
>
>
> Kranthi.
> http://goo.gl/e6t3
>
>
>
> On 1 March 2012 09:26, Kranthi Krishna <[email protected]> wrote:
> > Hi,
> >
> > Thanks for the input. I have seen some tutorials on joins, they all
> > suggest that MySql returns multiple rows
> >
> > For example
> > --------------------------
> > School | Board 1
> > --------------------------
> > School | Board 1
> > -------------------------
> >
> > Now if I have another one-to-many relation
> >
> > -----------------------------------
> > School | Board 1 | Type 1
> > -----------------------------------
> > School | Board 1 | Type 2
> > -----------------------------------
> > School | Board 2 | Type 1
> > -----------------------------------
> > School | Board 2 | Type 2
> > ------------------------------------
> >
> > Using UNIQUE or something similar (like php.net/array_search ) causes
> > problems when Type 1 = Type 2 etc.
> >
> > Kranthi.
> > http://goo.gl/e6t3
> >
> >
> >
> > On 29 February 2012 19:43, Michael Stowe <[email protected]> wrote:
> >> Select table1.item1, table2.item1 from table1 inner join table2 on
> table1.key = table2.foreignKey Where...
> >>
> >> You can also utilize left and right join to get data if there isn't a
> direct match (ie customer may not have ordered anything so you want to do a
> left join on orders as there may not be any order data but you still want
> to get the customer info).
> >>
> >> Hope that helps,
> >> Mike
> >>
> >>
> >>
> >> Sent from my iPhone
> >>
> >> On Feb 29, 2012, at 8:01 AM, Kranthi Krishna <[email protected]>
> wrote:
> >>
> >>> Hi all,
> >>>
> >>> Say I have an object like
> >>>
> >>> array
> >>>    schoolName => string
> >>>    board => array
> >>>         string
> >>>         string
> >>>
> >>> I generally create  two MySql tables
> >>>
> >>> schools: id PRIMARY KEY, SchoolName
> >>> boards: id FOREGIN KEY refers Table A(id), board
> >>>
> >>> and then do two selects. The problem is that, the number of selects
> >>> increase as the number of one-to-many relationships increase.
> >>>
> >>> Is there a better way to do this ? I have to extend an existing code
> >>> so I cannot use any libraries like doctrine
> >>>
> >>> Kranthi.
> >>> http://goo.gl/e6t3
> >>>
> >>> --
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