Actually, I think the behavior comes from the components used to connect to MySQL. Delphi doesn't really care one way or the other.
Dan Cumpian -----Original Message----- From: Paul DuBois [mailto:[EMAIL PROTECTED]] Sent: Thursday, December 19, 2002 1:41 PM To: [EMAIL PROTECTED] Cc: Dan Cumpian; 'Jeff Snoxell'; [EMAIL PROTECTED] Subject: RE: SELECT and UPDATE at the same time? At 13:23 -0500 12/19/02, <[EMAIL PROTECTED]> wrote: >Well, the only basis I have is personal experience from connecting to a local >MySQL database. The components I use for connecting to MySQL with Delphi does >cache the records as the server returns them. However, not all the records are >returned at once. As I said, it depends on how one connects to the server. Okay. If that's what you observe, I won't dispute it. But then the behavior is probably something specific to the Delphi interface. The underlying behavior of the client/server protocol is somewhat different than what you observe, so people using other APIs will likely see something different happening. > >If I'm wrong, then I apologize for any incorrect information that I may have >given. Just trying to help. > >Dan Cumpian > > > >On Thu, 19 Dec 2002 00:18:48 -0600 Paul DuBois <[EMAIL PROTECTED]> wrote: > >> At 23:43 -0500 12/18/02, Dan Cumpian wrote: >> >Jeff, >> > >> >Not if your outer loop is in a separate query. >> In that case, your query >> >is essentially a cursor and is static once >> OPENed. As you move from >> >record to record, what you are seeing is the >> records at the time the >> >query was opened. Now, if you were to update >> records that you haven't >> >processed yet, then they may show up as >> modified in your outer query >> >> Your basis for saying that? >> >> >because (depending on how you are connecting >> to the database) the server >> >only returns several hundred rows at a time >> and caches them as you go >> >> Your basis for saying that? >> >> >through the record set. But that doesn't sound >> like it will impact you. >> > >> >HTH, >> >Dan Cumpian >> > >> > >> >-----Original Message----- >> >From: Jeff Snoxell >> [mailto:[EMAIL PROTECTED]] >> >Sent: Wednesday, December 18, 2002 12:56 PM >> >To: [EMAIL PROTECTED] >> >Subject: SELECT and UPDATE at the same time? >> > >> >Hello again, >> > >> >I'm selecting a group of records from my >> database. I then loop through >> >the >> >selected records and do some work based on >> what I find. But what I also >> >want to do as I interrogate each record is >> update some of its fields >> >with >> >new values... but won't that screw up the >> outer loop? I mean if I try to >> > >> >execute a query whilst looping around the >> result set of a former query >> >will >> >I not screw up my result set that I'm looping >> through? >> > >> >Also, is it possible to update specific fields >> of certain records within >> >a >> >SELECT query? ie can I do something like this: >> > >> >SELECT * FROM my_table WHERE Age > 50 AND >> UPDATE Status = "OLD" >> > >> >Ta, >> > > > >Jeff --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
