Hello everyone,

I have 2 datasets that needed to be merged. Dataset A has unique IDs with multiple transactions for each ID. Dataset B also has unique IDs with multiple action of rating score at different time. I want to merge A and B using unique IDs. However it goes under a condition that date for each transactions must fall into the date range of rating action. For example, stock C got transactions on 01/01/2019 and 06/01/2019. It also got 2 actions of rating score on 06/01/2018 and 02/28/2019. So when merging stock C on transaction 01/01/2019 would get score that rated on 06/01/2018; transactions on 06/01/2019 would get score that rated on 02/28/2019.

Does anyone know how to approach this problem? Thank you so much!!!