RCP column order

SURA · Post by **SURA** » Sun Jul 24, 2011 10:20 pm

Hello all

Just I wish to know how the RCP will pick the columns? in order? or random?

Based on Key columns and then non key columns ?

Thanks
DS User

scope123 · Post by **scope123** » Sun Jul 24, 2011 10:38 pm

exact colum names is must. it can be any order.

jwiles · Post by **jwiles** » Mon Jul 25, 2011 11:39 am

Can you explain what you mean by "pick the columns"? Pick the columns when/where/under what conditions???? With a better understanding of what you are asking for, we may be able to give a more useful answer.

Regards,

SURA · Post by **SURA** » Mon Jul 25, 2011 2:51 pm

Thanks for the comment. I will give it in more detail.

Example: If i need to fetch the data from a table using RCP, just need to pass the connection details and table name. In that case whether the RCP will keep the column order as same as in the table or in different order?

This is my question.

DS User

jwiles · Post by **jwiles** » Mon Jul 25, 2011 3:20 pm

More than likely, although not absolutely guaranteed, the column order returned from the stage will match that of the table being read.

Just a point of education: RCP does not determine the order of columns in a data flow. That is actually determined by the operators (stages) themselves.
In most cases this will be the order in which the columns arrived at the stage's input links, and new columns generated by a stage will be added to the end of the virtual records (regardless of the order listed in the columns tab in Designer). You can see the virtual record schemas (and hence the order of the columns) in the job log by setting the environment variable OSH_PRINT_SCHEMAS=1.

The use of RCP really determines whether or not a modify adapter will be added to the output link during job compilation to keep only the columns defined in the columns tab (metadata grid) on the stage's output links.

Regards,

SURA · Post by **SURA** » Mon Jul 25, 2011 5:05 pm

Thanks for the clarification.

DS User