joiners multiplying the base lines

I have a database with four columns and I want to ingest some data from another database. When I do the join, some of the data is found and others are not, so I need to reduce the search key from 4 to 3 elements, then from 3 to 2, being less disaggregated, but the base is being multiplied and the number of lines is more than fold. How to solve?

Hi @Thiago_Barbosa,

welcome to the community. In order to assist you as best as possible, would be be so kind to share a screenshot of your joiner please?

Best
Mike