How to use SQL Lag Function concept in talend

[RAJ6]

Hi Talend Folks,

• How to use Sql LAG function concept in talend.
• The Lag function gives the previous column values based on ordering. 
• please check below link you will get clear idea for Sql LAG function
• http://www.c-sharpcorner.com/UploadFile/f82e9a/lag-and-lead-functions-in-sql-server/
• How to do this requirement in tmap component or some other component?

[Anonymous · Accepted solution]

Hi there,

This sort of thing can be done very easily in a tJavaFlex component, as follows.

The tFixedFlowInput generates rows with a single Integer column:

Add a new column to the output schema of th tJavaFlex component for the LAG value:

And the the following code will output the previous (LAG) value, before setting it to the current value of newColumn, which will be available when the next row is processed:

Regards,

Chris 

[Anonymous]

use sort before that to get lead functionality..