Difference between JOIN,LOOKUP,MERGE?
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Answer / rajesh pandi
1.if a source have huge volume of datea, then that time we have to use join, or merge stage
2.if you want to filter the unmatched record from reference files, then we should use merge stage only
3.join stage can have 'n' number of input link(1 left link 1right link other links called intermediate link) but only one output link...
Merge stage cane have 'n' no of input link (1 master link n update link) and one output link And equal no of reject link as same as update link
Look up stage can have n number of input link and 1 output link and one reject link
4.join we can do all join operation inner, left outer, right outer, full outer but in merge and lookup we can only do a inner join and left outer join
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Answer / rajesh pandi
1.if a source have huge volume of datea, then that time we have to use join, or merge stage
2.if you want to filter the unmatched record from reference files, then we should use merge stage only
3.join stage can have 'n' number of input link(1 left link 1right link other links called intermediate link) but only one output link...
Merge stage cane have 'n' no of input link (1 master link n update link) and one output link And equal no of reject link as same as update link
Look up stage can have n number of input link and 1 output link and one reject link
4.join we can do all join operation inner, left outer, right outer, full outer but in merge and lookup we can only do a inner join and left outer join
| Is This Answer Correct ? | 0 Yes | 0 No |
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