如何仅使用一个匹配的关联表行来加入父项

Question title isn't the best. I have two parent tables A and B and their association table AB. I need columns from A and B, none from AB. For a given row in A, the multiple matching rows in B will always have identical values for the columns I want. Currently, I join the 3 tables and do a DISTINCT on B, but it is incredibly time-consuming. Here's example data:Question title isn't the best. I have two paren