[Zope-DB] Problem selecting Oracle LOB's

[Jorge O. Martinez]

Matt:

You are absolutely right. I looked at the source, and this is coming 
back as well:

<tr>
   <td>44</td>    <--- THIS IS WHAT I SAW
   <td><Products.DCOracle2.db.LobLocator instance at 996494></td>
			(DIDN'T SEE THIS)
</tr>

I'll try what you suggest. One question though. How do I call the 
'select' method? Does this look correct to you:

<dtml-in select>
<dtml-var Products.DCOracle2.db.LobLocator>
</dtml-in>

Thanks for your quick and accurate response,

Jorge M.

Matthew T. Kromer wrote:

> Jorge O. Martinez wrote:
> 
>> (I am resubmitting this question because I had initially sent it with 
>> the wrong subject, and figured people would think it's the same 
>> subject. Sorry about that).
>>
>> Hi:
>>
>> I have been able to install Zope, DCOracle2, and was able to make a 
>> connection to the DB, and execute simple queries displaying results 
>> just fine.
>>
>> However, I have not been able to get LOB's to work. I am following the 
>> examples from Peterb in:
>>
>> http://www.zope.org/Members/peterb/oracle_lobs
>>
>> I am trying to do a select blob, and I get the template to display the 
>> id (which is the argument I pass), but don't get anything for the 
>> knowledge_text (the LOB, which is only text), this is what I am getting:
>>
>> KNOWLEDGE ID KNOWLEDGE TEXT
>> 44
> 
> 
> 
> I bet if you view source, you'll see the tag <LobLocator ...> as the 2nd 
> argument, which the browser is hiding because it thinks its a tag.
> 
>>
>> SQL used:
>> SELECT
>>   knowledge_id, knowledge_text
>> FROM
>>   knowledge
>> where
>> knowledge_id = 44
>>
>>
>> I know it must be my error because I think I am not calling the 
>> "select" Python script correctly; I've tried several different ways, 
>> and get all kinds of errors. Anybody outthere knows what is the 
>> correct way to call it from the Z SQL Method? This is what I have in 
>> my Z SQL Method:
>>
>> ------------
>>
>> SELECT
>>   knowledge_id, knowledge_text
>> FROM
>>   knowledge
>> <dtml-sqlgroup where>
>>   <dtml-sqltest knowledge_id op=eq type=int optional>
>> </dtml-sqlgroup>
> 
> 
> 
> Because you test something named knowledge_id, you have to pass it in as 
> a parameter... see below
> 
>>
>> <dtml-in select>
>> <dtml-var sequence-item>
>> </dtml-in>
>>
>> ** I am including 1 of the ways how I tried to call the 'select' 
>> script but it does not work**
>>
>> ------------
>>
>> And this is the code in the select Python script (same from the sample 
>> code). I've tried many different ways, this is just the latest:
>>
>> # Manually iterate over whole result set, copy into list of dicts just
>> # like dictionaries()
>> # except we also read all BLOBs in their entirety and put in the 
>> value, # not the LobLocator
>>
>> result = []
>> for row in container.sql_select_blob(id=id):
>>   lob = row['blob']
>>   result.append({'id': row['id'], 'blob': lob.read()})
>> return result
> 
> 
> 
> You want
> 
> for row in container.sql_select_block(knowledge_id=id)
> 
> ... presuming ID is the value you want to search for.  It has to match 
> the definition of the SQL method.
> 
> Otherwise what you're doing is correct.
> 
> Note that the latest DCOracle2 is "most correct" in CVS; I can't 
> remember if there was a broken-ness to the LOB support in PR1.
> 
>>
>> ** Note, I've tried this way, and also replacing the 'id=id' for 
>> 'id=knowledge_id', but it did not work, also I replaced the 'blob' for 
>> 'knowledge_text' (my blob), but it doesn't like it **
>>
>> I am new to Python and Zope, hence this basic question. I am sure it 
>> must be something simple, so thanks for your patience,
>>
>> Regards,
>>
>> Jorge M.
>>
>>
> 
> 


-- 
Jorge O. Martinez
MIS Senior Associate
eMediaMillWorks
1100 Mercantile Lane, Suite 119
Largo, MD 20774
E-mail  => jmartinez@eMediaMillWorks.com
Phone   => (301)883-2482 ext. 105
Fax     => (301)883-9754