ETL Testing Automation using XML's
Can any one have idea how to automate ETL testing like ...compare schemas, data, lookups and making sure the data flowed correctly end to end without truncations, calculation errors. please provide clear details how to automate.
I would start by looking at redgate's suite of tools. They have a tool to compare databases, and a tool to compare data in databases, as well as documentation on how to do so. You can compare tables as well as results of specific queries, which will help you find truncation errors. To test calculation errors, you would need to execute some queries that calculate the values yourself, and compare that to the actual values. How you do this depends a lot on the actual calculations that need to be done. There are a number of approaches to do this in an automated way. One would be to write some code that connects to the database, queries it, calculates the correct values and then compares to the stored values. You could then run this code with junit or nunit, or whichever test runner for whatever programming language you use.