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Posted by cdtsly on 06/14/23 11:50
in fact, i need this order because i am rebuilding a table and i need
to do this way
i have a workaround with generating no fetch of all the table, but to
select the rows one by one
which give a stupid number of query( 200 000 rows=>200 000 query) and
it take a lot of time naturally :-)
i made this example to show my problem
is not there a possibility to fetch a special way which can take in
consideration freshness?
Kimmo Laine a écrit :
> <cdtsly@relayeur.com> wrote in message
> news:1150450217.111881.169080@c74g2000cwc.googlegroups.com...
> > the update works for the updated column
> > but as you say the prefetch row are already there
> > so the mysql_fetch_array command will take a line where there is not
> > anymore the str=4 value
> >
> > i know why i have this problem and i like to know how not have it
> > :-)
>
>
> Run the queries in different order. First update, then select.
>
> like this:
>
> $query7="UPDATE val SET str='7',updated='1' WHERE val='2'";
> $result7=mysql_db_query($datamysql,$query7);
>
> $query="SELECT * FROM val WHERE str='4'";
> $result=mysql_db_query($datamysql,$query);
>
> while ($row=mysql_fetch_array($result))
> {
> $str=$row["str"];
> $val=$row["val"];
> $query2="UPDATE val SET str='5' WHERE val='$val'";
> $result2=mysql_db_query($datamysql,$query2);
> }
>
> Well actually, to keep it very very very simple, you could just do this:
>
> $query7="UPDATE val SET str='7',updated='1' WHERE val='2'";
> $result7=mysql_db_query($datamysql,$query7);
>
>
> $query2="UPDATE val SET str='5' WHERE str='4'";
> $result2=mysql_db_query($datamysql,$query2);
>
> And nothing else. If you want to update all rows where str='4', then use
> that as the condition, you don't need to first select something with one
> condition, and then one by one row update all the rows. You can do it all in
> one update query.
>
> --
> "ohjelmoija on organismi joka muuttaa kofeiinia koodiksi" -lpk
> spam@outolempi.net | Gedoon-S @ IRCnet | rot13(xvzzb@bhgbyrzcv.arg)
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