[Zope] strange sql problem

[Dieter Maurer]

Aseem Mohanty writes:
 > ...
 > The problem is if I place A in join_sql_methods it works perfectly and 
 > returns me the relevant data item. However if I place A in 
 > util_sql_methods it returns an empty result set.
 > 
 > My DTML method looks like
 > 
 > <dtml-call "B">
 > <dtml-call "join_sql_methods.A"> in the former case
 > 
 > and
 > 
 > <dtml-call "B">
 > <dtml-call "util.util_sql_methods.A"> in the latter case.
I strongly recommend background reading (Zope book or

  <http://www.dieter.handshake.de/pyprojects/zope/book/chap3.html>

) and much more care when programming or problem reporting!


First:

     when you use "dtml-call" you should not expect any result!
     It discards any return values.
     Both cases above will not show anything.

Second:

     when you use a ZSQL Method inside "...", it is not
     automatically called. You need to do it explicitly.
     Otherwise, you get the ZSQL Method itself (and not its
     result).

Try: '<dtml-var "_.len(XXXX.A())">'.


If you were careful when programming and only careless when
reporting your problem, you may use the "src__" parameter of
Z SQL Methods. When set to a true value, the method will return
the generated SQL command but not execute it.
This is often very helpful to analyse problems with Z SQL Methods.


Dieter


PS: At least me, I expect that problems are reported with great care.

    This means, that your problem report should contain "dtml-var",
    when your DTML code does.

    Only carefully prepared problem reports provide the base
    for an efficient response.