RE: better sql code
- From: "Mark W. Farnham" <mwf@xxxxxxxx>
- To: <raja4list@xxxxxxxxx>, "oracle list" <oracle-l@xxxxxxxxxxxxx>
- Date: Tue, 25 Oct 2005 14:06:34 -0400
Okay, my first response was a little terse.
First, I hope you realize that you are actually starting sqlplus and running
through the security and session establishment code for each row. (If this
was a practical joke question, I didn't recognize your name and you've
bagged me.)
Second, I'm wondering whether "list" contains an account for each row of
adtstage. If it does, then you don't need "list" at all. If it doesn't, then
you should either filter the input to sqlloader or also load "list" into a
table. Whichever is easier for you.
Option A: (All of adtstage to be processed once it is in Oracle)
update hsp a
set adt_flag='Y',
(mr#, facility_code, patient_lname, ..., ....) =
(select
mr#, facility_code, patient_lname, ..., ....
from adtstage b
where a.acct# = b.acct#
)
where hsp_id='XXX'
and acct# in (select acct# from adtstage);
Option B: (Adtstage contains some rows not to be updated, and list controls
which rows to use)
Just change "adtstage" to "list" in the last line.
I just typed this in quickly and didn't test it. The main point is to log in
once. The secondary point is to let Oracle use sets. Whether this would be
faster via external tables seems unlikely to me since the correlated
subquery will want the index, and someone giving this problem more thought
can probably do it better.
Third, it also seems a little odd to me that you're updating mr# if it is
indeed part of the pk. I'm guessing you're a bit new at this, unless, as I
said, this is a practical joke.
Perhaps you don't really want it in the set list and the "and" predicate
should be:
and (acct#,mr#) in (select acct#,mr# from adtstage)
Regards,
www.rsiz.com Oracle Technology and Business
Consulting
Mark W. Farnham
President Rightsizing, Inc.
36 West Street
Lebanon, NH 03766-1239
mwf@xxxxxxxx tel: (603) 448-1803
Want a signature like this?
-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx
[mailto:oracle-l-bounce@xxxxxxxxxxxxx]On Behalf Of raja rao
Sent: Tuesday, October 25, 2005 1:16 PM
To: oracle list
Subject: better sql code
Hi All,
can someone give me a better code for the below:
We use the sqlloder to load somedata into oracle.
that will be loaded into a stage table called adtstage.
Later this should be updated into the main table HSP.
For this purpose, we have develped the code like this.
we will collect the acct# numbers into a flat file (filename is list) and
for each line will fire theupdate statement like below.
cat list|while read line
do
sqlplus -s <<EOF
${connect_string}
@update.sql ${line}
EOF
done
# list is a file which contains the acct# to be updated into main table.
update.sql contains teh below code:
define hsval=&1
update HSP set
mr#= ( select mr# from adtstage where acct#= &hsval ),
facility_code=( select facility_code from adtstage where
acct#= &hsval ),
Patient_LName= ( select Patient_LName from adtstage where
acct#= &hsval ),
.....
adt_flag='Y'
where acct#= '&hsval' and hsp_id='XXX'
;
commit;
In teh abvoe both tables, acct#, mr# columns are primary key.
There are around 100 cols to be updated from stage to main tables. If
there are a 1000 records it is taking
long time to update the main table. Becoz, it should run thru the whole
1000 recods and run the above update
which is taking lot of time.
can someone help me in tuning this.
Thanks,
Raj
NOTE: Both the tables HSP and ADTSTAGE are same structures and they have
acct#, mr# as the primary key.
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