Re: basic questions with odbc and visual basic.

The traditional hack for faking a unique key is to add a timestamp
column to the database table in question-- unique indexed - with a
default timestamp of Now().

Gary Doades wrote:

>On 27 Sep 2004 at 16:42, Merlin Moncure wrote:
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>>>For manipulating the data -- Access works pretty good as long as
>>>
>>>
>>Access
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>>>can know which record(s) to update (primary keys or OIDs -- that sort
>>>
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>>of
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>>>thing).
>>>
>>>
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>>Looking deeper it seems all my problems are really boiling down to one
>>problem: the where clause used to update the edited record back to the
>>server. Both access and vb generate a where clause that includes every
>>field in the table instead of the p-key. For various sundry reasons
>>such as improper handling of null values, etc. this where clause gets
>>busted. This problem is aggravated by the fact that all my domains get
>>treated as text types, although this is correctable by using a view
>>which I was planning to use anyways (aside: I make heavy use of
>>domains). This busted where clause trips up vb and access in different
>>ways. This may be a case where I may want to explore hacking the odbc
>>driver to get it to do what I want, depending on who is building the
>>clause. My guess is the ado driver is building it so I'm basically
>>hosed. It's really queer to me that they use the p-key to pull the data
>>out and the entire record to write the data back...what's the point of
>>the p-key anyways?
>>
>>The odbc driver is supposed to have a property exposed to the ado
>>wrapper that allows you to constrain the write-back where clause to
>>different things, but apparently this does not work in pgsql-odbc.
>>
>>I tried the ole db driver and got nowhere, couldn't even get a basic
>>connection. Hopefully I can get this corrected and work with this
>>driver a little bit. I have about two weeks to figure out the best way
>>to proceed. So far, I'm really unimpressed with the ado architecture,
>>this being my first real experience with it (as compared to ado.net,
>>which is a dream to work with).
>>
>>
>>
>
>The only reason the ADO driver would build an update statement using
>all columns is that it can't identify a unique key (primary key). It's
>possible that the ODBC driver does not correctly supply this info.
>
>Can you do something artificial like put an additional unique index on
>the primary key?
>
>As a last resort you might try a commercial ODBC driver for postgres
>,openlink I think for one, to see if this helps. At least it may give pointers
>to the real problem. ( you can get a trial copy for a while I think)
>
>Cheers,
>Gary.
>
>
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