DSXchange

Hi all,

For incremental extraction from source,

i take the last run's date in a text file, which can be used as reference in lookup and i can pick up the records which have greater date than that from the source. If there is a table for keeping the last run's date value means, then there is no need for lookup i can take using that in the query itself. Is there any way i can do the logic with text file in the source itself. please advise.

Thanks,
Ram

Read the text file and pass the value in as a job parameter, then bind the parameter value into your source sql.

Hi chulett,

How to update the parameter file everytime. If we create a parameter set for this specifically, how to access it. Please explain the logic. Is the parameter set will be a text file. And in the value tab of the parameter set i have to give the initial value and update it everytime?. If its unix i can update using "> standard output syntax ". What in case of windows, should i create a new file and delete the existing one.

Thanks in advance

The > redirection operator is just as valid in Windows.

The approach is to use a DataStage job or routine or execute command activity to populate this file.

There is other option apart from provided by other readers. You can use the control table and that should be populated initially at every run of your jobs/sequence and in your table you can add a column update_date whose value should be passed from DS transform DS job start date. Use pre SQL in your jobs to check the records date with the update_date column because it is not yet updated. and at the end of your jobs update the control table with the update_date, so every time ur control table will have last_update date and current date apart from first run where u have to set initial default value and you can use those dates in pre and post SQL to get ur desired result.

Well, the other readers answered the question as asked.