Best way to add a column conditionally to a sequential file

[bondlee]

Hi All,

I have a specific requirement of adding a column conditionally to a target sequential file. I am looking for the best way of doing it.

To put it in detail, the source can have two columns Col1, Col2. Col1 always goes to target file (which is a sequential file) but Col2 should be added to target only if it satisfies a condition. Assuming that there is only one record in source, what will be the best way to achieve this?

I think we can't use RCP as it is blocked by the conditional addition of the column on contrary to unconditional addition.

I have a workaround using sequences but I am interested to see if there is any better way. Appreciate your interest in this.

[ray.wurlod]

For this to work you must set "First line is column headings" to False.

Always send one column. It may be derived as InLink.Col1 or it may be derived as InLink.Col1 : "," : InLink.Col2 in a Transformer stage.

Wrap these two possiblilties in an If..Then..Else construct to manage your condition, and amend the delimiter character appropriately.

[SURA]

I like this approach Ray.

[chulett]

Interesting. You could also conditionally write out the header record as well if desired.

[ray.wurlod]

Yes, either in a before-job subroutine or when processing row #1.

In the former case the Sequential File stage would need to be set to Append to the file.

[bondlee]

Thanks all for the replies. Sorry for late reply.

@Ray, It's a nice approach. I was also thinking of column export and import stages for similar approach. I was wondering, however, how can we generate record of column names in the latter case (while processing row#1). I guess for this we might need to use either a row generator stage or a funnel stage after transformer.

I hope you are suggesting to use a record delimiter for row#1 like below:
If Row#=1 Then <Col_Names> <Rec_Delim> <Col_Values>

[ray.wurlod]

Yes, that's my suggested approach (once I'd understood your # to belong to "Row" and not to "=").

[chulett]

(once I'd understood your # to belong to "Row" and not to "=").

'Not' being the operative word here.