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From: michael dot x dot peppler at jpmchase dot com
Subject: RE: Is there a performance advantage to using placeholders with Sybase?
Date: Jan 8 2008 11:10AM

OpenClient can do array binding, though I've never used it.

For execution of RPC (procs using placeholders) you must use the form 
"exec procname ...".

And lastly - if you are using FreeTDS then most of this (placeholders, 
array binding, RPC execution) doesn't work anyway, because FreeTDS's 
implementation of OpenClient isn't complete in this respect (or at least 
wasn't last time I looked - I have to admit that I don't really look all 
that often...)

Michael




"Ed Avis"  
08.01.2008 11:48

To
, 
cc

Subject
RE: Is there a performance advantage to using placeholders with Sybase?






Michael Peppler wrote:

>I haven't checked execute_array vs execute - off-hand I don't 
>think that there would be any real performance advantage. 

In some DBDs execute_array() is implemented to have just a few round trips 
to the database rather than one per row.  To get that with Sybase I 
imagine you must use bcp.

>For emulating placeholder behavior in more complex T-SQL code 
>- sure it could be done, but it would mean a lot more syntax 
>analysis in the prepare() code itself,

I think an explicit flag would be needed somehow because parsing other 
people's SQL is a pain.

Hmm, I did an experiment:

    my $sth = $dbh->prepare('my_stored_proc ?');
    $sth->execute('x');

No error was raised even though I connected with RaiseError and 
ShowErrorStatement.  I am using DBD::Sybase with freetds to connect to 
MSSQL.

-- 
Ed Avis  

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