[Zope-DB] Re: dtml-let variables in sql queries

[Jonathan]

----- Original Message ----- 
From: "Andreas Tille" <tillea at rki.de>
To: "Jonathan" <dev101 at magma.ca>
Cc: <zope-db at zope.org>
Sent: Thursday, November 23, 2006 11:03 AM
Subject: Re: dtml-let variables in sql queries


> On Thu, 23 Nov 2006, Jonathan wrote:
>
>>> <params>name nameid
>>>
>>> </params>
>>> SELECT * FROM names
>>> WHERE fake = 0
>>> <dtml-if name>
>>>   AND <dtml-sqltest name op=like type=nb>
>>> </dtml-if>
>>> <dtml-if nameid>
>>>   AND <dtml-sqltest nameid op=eq type=int>
>>> </dtml-if>
>>
>> First off, i would highly recommend using python scripts instead of DTML 
>> for the kind of processing you have described.
>
> You are right here and I would definitely prefer Python scripts.  The
> problem is that I'm using the Formulator Product and despite there are
> descriptions how to use it with Python scripts I failed while it was
> very straigtforeward to use DTML (in fact, this is the only part of
> my application in DTML).  I just stripped down the application to a
> very simple example and avoided Formulator magic which is obviousely
> not the source of the problem.
>
>> That said,  you have not described the GetCases method.
>
> I forgot to mention the name.  It is the code snipped above.
>
>> If GetCases is the name of your SQL method, then you need to pass in the 
>> parameter 'nameid'
>
> Well, nameid is not explicitely passed but taken from the parent
> out of
>
>     <dtml-let nameid="REQUEST.form['nameid']">
>
> and this works.  The problem is that name which is builded
> out of
>
>     <dtml-let namepart="REQUEST.form['namepart']">
>          Namepart = <dtml-var namepart><br />
>          <dtml-let name="namepart + '%'">
>
> is ignored by the SQL method and I fail to see the difference.
> The <dtml-if name> seems to be false in any case.

It may be due to the fact that the 'let' statement creates a variable in 
another part of the 'namespace' (ie. not in the REQUEST namespace).  You 
could test this theory by replacing the dtml-let with a dtml-call 
REQUEST.set

eg.
     <dtml-let namepart="REQUEST.form['namepart']">
          Namepart = <dtml-var namepart><br />
          <dtml-call "REQUEST.set('name', namepart + '%')">


hth

Jonathan