DSXchange

Hi

I wanted to know the when can we use the JOINER AND LOOKUP.

I am new to DS. I am studying the Pdf's .

What is understood is if reference link haveing more data we should go to Joiner.

My doubt is that if we use in-memory method in Lookup then only it takes the whole data to server memory and lookup's the input link. If we use Sparse method, it doesn't take the whole data to server memory.

thts correct ...for more information you can search the forum ..

Join , Lookup and merge have lot of similarities.

Regards
Sreeni

... but very important subtle differences.

1.join will take only one partition data of master (reference table) at a time in memory where as lookup (sparse) take all the data in to memmory

2. We can have reject link in lookup . not possible in joiner

3.joiner is good if data volume is huge.

The Join, Lookup and Merge stages combine two or more input links according to values of key columns. They differ mainly in memory usage, treatment of rows with unmatched key values and input requirements i.e. sorted and de-duped

Francis