look up error

[rahul8055]

reference link tech_data of look up stage unique_data must have key fields defined

can anyone help me with this...I looked into the forms but couldn't find any


thanks
Rahul

[gateleys]

If you do not specify the key field, how do you expect the matching to take place?

[rahul8055]

If you do not specify the key field, how do you expect the matching to take place?

Do I need to specify it as primary key?
can you please expand your answer


thanks,
Rahul

[rahul8055]

If you do not specify the key field, how do you expect the matching to take place?

Do I need to specify it as primary key?
can you please expand your answer


thanks,
Rahul

There is one column from the master and 6 columns from the reference
and one column in common .

I used these columns for mapping.

thanks
rahul

[gateleys]

If you do not specify the key field, how do you expect the matching to take place?

Do I need to specify it as primary key?
can you please expand your answer


thanks,
Rahul

yes.

[rahul8055]

If you do not specify the key field, how do you expect the matching to take place?

Do I need to specify it as primary key?
can you please expand your answer


thanks,
Rahul

There is one column from the master and 6 columns from the reference
and one column in common .

I used these columns for mapping.

thanks
rahul

Hi gateleys,
It was not allowing me in the reference link I mean in the 6 columns to assign one of them as primary key but now I used a key expression which helped me to use that particular key as a primary key
Is that the problem?

Thanks,
Rahul

[chulett]

It's got nothing to do with Primary Keys or any kind of indexing, but rather fields marked as Key Fields. They are the ones that will be bound into the 'where' clause of your lookup sql.

[rahul8055]

It's got nothing to do with Primary Keys or any kind of indexing, but rather fields marked as Key Fields. They are the ones that will be bound into the 'where' clause of your lookup sql. ...

Hi chulett
The mainstream is a table from database which has 6 columns
and the reference stream is a file with 1 column. They both have a common column and that one is marked as a key in the mainstream input.
The query used is select 1,2,3,4,5,6 from tablename.

In the output of the lookup mapping I match the 1 column from file and rest 5 from the table. and I got this error....this is the complete scenario...
and the error is

reference link tech_data of look up stage lookup _unique_data must have key fields defined

reference link is the file

Thanks,
Rahul

[Sainath.Srinivasan]

If you go the sequential file stage column properties, have you marked the key field with a tick in the box ?

[rahul8055]

If you go the sequential file stage column properties, have you marked the key field with a tick in the box ?

yes I marked the key field but when I mark it I get a new error

Error Preprocessing primary key derivation for stage look_up

More from the error:-column:-unique_row_id
The supplied expression was empty

Thanks,
Rahul

[Sainath.Srinivasan]

That is because your lookup stage does not have the 'field link' between main and reference links.

I recommend you to undergo DataStage training. Earlier the better.