Which type of join returns all rows from the primary pipeline and matches to rows in the imported pipeline?

The left outer join is the type of join that returns all rows from the primary pipeline while matching to rows in the imported pipeline. In this scenario, the primary pipeline serves as the starting point, and the left outer join ensures that every record from this dataset is included in the final output, regardless of whether a corresponding record exists in the imported pipeline. If there are matches in the imported pipeline, the respective values will be incorporated; if there are no matches, the result will still display the records from the primary pipeline with null values for the missing data from the imported pipeline.

This behavior of retaining all records from the primary dataset is fundamental to understanding how left outer joins function in data manipulation. It contrasts with inner joins that only return rows when there is a match in both datasets, potentially omitting valuable information from the primary pipeline that doesn't have corresponding entries in the imported data. Similarly, right outer joins focus on all entries in the imported dataset, ignoring unmatched rows from the primary dataset, which is not the requirement outlined in this question.