Posted by Jerry Stuckle on 01/02/08 02:18

Aaron Gray wrote:
> "Jerry Stuckle" <jstucklex@attglobal.net> wrote in message
> news:m_Wdnblb4PlxcufanZ2dnUVZ_gWdnZ2d@comcast.com...
>> Aaron Gray wrote:
>>> "Rik Wasmus" <luiheidsgoeroe@hotmail.com> wrote in message
>>> news:op.t392n4xa5bnjuv@metallium.lan...
>>> On Wed, 02 Jan 2008 01:50:20 +0100, Aaron Gray <ang.usenet@gmail.com>
>>> wrote:
>>>
>>>> I have a MySQL table of pages each with a 'title' and 'page' fields.
>>>>
>>>> How do I do either an UPDATE if the pages 'title' exists or an INSERT if
>>>> it
>>>> does not ?
>>>>
>>>> The code I have written does not seem to do the job correctly.
>>>>
>>>> $result = mysql_query( "SELECT page FROM pages WHERE title = '" .
>>>> $title
>>>> . "';");
>>>>
>>>> $row = mysql_fetch_array( $result, MYSQL_ASSOC);
>>>>
>>>> if ( isset( $row["title"]) && $row[title] == $title)
>>>> {
>>>> $result = mysql_query( "UPDATE pages SET page = '". $page . "'
>>>> WHERE
>>>> title = '" .$title . "';");
>>>> if ($result)
>>>> mysql_query( "COMMIT;");
>>>> }
>>>> else
>>>> {
>>>> $result = mysql_query( "INSERT INTO pages SET title ='" . $title
>>>> .
>>>> "', page = '" . $page . "';");
>>>> if ($result)
>>>> mysql_query( "COMMIT;");
>>>> };
>>>>
>>>> This code is buggy and doing an insert rather than an update. How would
>>>> you
>>>> approach this task ?
>>> It could be done with one easy query, look into ON DUPLICATE KEY
>>> UPDATE
>>> syntax, ask in comp.databases.mysql
>>>
>>> I need to keep the logic in PHP rather than using SQL.
>>>
>>> Aaron
>>>
>>>
>>>
>> Why? SQL is the correct place to handle this.
>
> I need to know whether I have a new page or not and I need concurrency in
> the PHP to know whether a page is already being editted and I need to keep a
> log of transactions.
>

OK, if you need to find out if you have a new page or not, you've got to
query the database to see if it exists. But you've also got to be
careful, because someone could insert the same page between the time you
query and the time you insert. Sure, it's a small period of time, but
it can still happen.

And you can't tell for sure if a page is being edited or not. All you
can really tell is if it has been edited.

> At this stage in my apps life, prototype phase I prefer to keep this llogic
> in the PHP code.
>
> Aaron
>
>

That's doing it the hard way. Use the tools available to you.

--
==================
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Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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