[GRASSLIST:4476] How can I speed this up?

Craig Aumann caumann at ualberta.ca
Wed Oct 6 18:03:25 EDT 2004


The code is very simple:


for MYCAT in `echo "select distinct avicat from allpoly_att"|db.select
-c`;  do 
    echo $MYCAT
    AGE=`echo "select age from play_att where link_key = $MYCAT" |
db.select -c`
    COVER=`echo "select cover from play_att where link_key = $MYCAT" |
db.select -c`

    echo "update allpoly_att set age = $AGE where avicat = $MYCAT" |
db.execute
    echo "update allpoly_att set cover = $COVER where avicat = $MYCAT" |
db.execute
done


Right now, it is doing about 2 updates per second - which is too slow! 
Is the slowness caused by piping it through db.execute?   

Other suggestions for speeding this up?

Cheers!
Craig





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