regarding utility hashlookup

vijaykumar · Post by **vijaykumar** » Wed Jan 03, 2007 4:47 pm

Hi Gurus,
I read that utilityhashlookup does lookup operation against a hashtable.

my design is odbc------>hashed file.

used another odbc source and want to join with hashed file.

i want to make use of utility hashlookup which does lookup against a hashtable.

from where i should call this utility, so that it does lookup against the table stored in my hashed file.

cheers;
vijay

ray.wurlod · Post by **ray.wurlod** » Wed Jan 03, 2007 5:12 pm

In the Transformer stage that you have not yet included in your design.

However, it would be far more efficient to use a second Hashed File stage in the job design, and use the Transformer stage to perform the lookup against it. In this way, you do not incur the overhead of the routine, and possibly gain the benefit of the hashed file read cache.

vijaykumar · Post by **vijaykumar** » Wed Jan 03, 2007 5:13 pm

hi gurus,

i need to make use of utilityhashlookup, i never used this utility.
i have seen from previous forums that it does lookup against hashtable.
i have dumped table for ex: employee in hashedfile.
from where i should call this utility.
i never used this utility, i want to make use of this utility and analyze how it works.
plz gurus i would appreciate if anyone help me in analyzing this utility.

cheers;
vijay

ray.wurlod · Post by **ray.wurlod** » Wed Jan 03, 2007 5:16 pm

vijaykumar wrote:i need to make use of utilityhashlookup

You don't. It's the wrong answer to your requirement.

Source code is provided in the repository; examine it if you want to understand what it does and how it works.

Saama · Post by **Saama** » Wed Jan 03, 2007 5:17 pm

hi gurus,
in the transformer properties , i got tabs only to specify before sub-routine or after sub-routine, how should i call utilityhashlookup.
plz help me gurus in analyzing.

cheers;
vijay

ray.wurlod · Post by **ray.wurlod** » Wed Jan 03, 2007 5:18 pm

It's a transform function and therefore can not be invoked as a before/after subroutine.

vijaykumar · Post by **vijaykumar** » Wed Jan 03, 2007 5:40 pm

HI GURUS,
my design is hashfile---->ODBC
combining hashfile with ODBC with transformer stage.
i want to make use of utilityhashlookup.
iam defining the properties at column deptno.

deptno-->doubleclick--->browse for functions and i specify the expression as UtilityHashLookup('SCOTT.DEPT', DEPTNO, DSLink15.DEPTNO).
i cannot validate my expression.

my keycolumn is deptno

my name of hashtable--->scott.deptno

i couldn't understand the term- position to be retained.plz help me in validating the expression and also in analyzing the utility.

cheers;
vijay

us1aslam1us · Post by **us1aslam1us** » Wed Jan 03, 2007 6:10 pm

Check this post, Ken had given a beautiful explanation. Search is a best approach for all your questions.

viewtopic.php?t=101154&highlight=utilityhashlookup

Sam

DSguru2B · Post by **DSguru2B** » Wed Jan 03, 2007 9:30 pm

Pay close attention to Ray's comment. Just because you have it, does'nt mean you 'have to have to' use it. Just source the odbc, do a lookup on the hashed file using the conventional design via transformer