In live agile and waterfall project, how can we perform regression testing successfully ?
Regression test pack is the key to ensuring minimum work product and functions are not impacted adversely with new code/function introduction and/or amend to existing code/function.
Agile and waterfall project design (plan) to include appropriate time duration at intervals (depending on project scope and related function delivery) for regression testing.
which test cases we need to execute and how to maintain the regression testing folder ?
Master regression folder for current production code to test for new release back-out at anytime.
Multiple regression folder based on application release/test in progress concurrently, with some requiring to be merged as final new release.
should we do full regression testing or partial regression?
Regression testing (with risk based testing approahc) in full recommended, as feasible.
Partial would be specific to sub-functions and below, with assurance of no code changes (you can utilize code compare tools for verification of such).
how to prioritise regression testing if time is less?
Regression testing is a priority. Automation (including test data/test data refresh) of regression test suite would be key to incorporate maximum. Project design/plan to allow sufficient time, rather than priortize based on less time. TIme for completing regression testing would be known, whether manual/automated/hybrid, to be planned for accordingly.
what are the best practices to successfully do regression testing in a agile project
Apply all above concepts to determine right solution for waterfall and agile project.
At minimum, regression to ensure minimum overall function (N-1 release) and sub-function (update/new) in agile release/sprint is tested as progressing ahead.