sybperl-l Archive

From: "Ed Avis" <eda at waniasset dot com>
Subject: RE: Is there a performance advantage to using placeholders with Sybase?
Date: Jan 8 2008 3:09PM

Steven Wechsler wrote:

>I am working on a script to recover whatever data I can on a 
>table that has "692" errors (similar to the "605" error, the 
>bane of every Sybase
>DBA) by querying the corrupt table based on explicit key 
>values and retrieving each row that I can. This can't be 
>batched in SQL because once that error hits the SQL batch is 
>terminated, but in Perl I can take action based on that error 
>(try to retrieve the data from a different server which has an 
>older version of the table).

Ah, I see - you have some unusual requirements :-(.

I guess you could try a binary search across key values, if there are lots of them and only a few rows are bad.  You could try running your script on the server host itself to cut network latency.  Instead of a lengthy insert query you could just 'select some_col from bad_table where key = ?' and use that to make a list of good keys and bad keys.  Once you have the list of good keys getting all the data out will be straightforward using a temp table and a single select query.

But anyway, I guess calling a stored proc using CTlib directly as discussed earlier in this thread is the fastest way to run such a proc.

-- 
Ed Avis  

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