What type of data combination occurs in a left join?

In a left join, the primary focus is on the left table, where all records from this table are retained in the result set. For each of these records, the query tries to find matching records in the right table based on the specified join condition. If there is a match found, the data from both tables is combined in the output; however, if there is no match in the right table, the corresponding fields from the right table will contain null values.

This ensures that the output contains every record from the left table, regardless of whether there is a corresponding match in the right table. Thus, the correct answer illustrates that during a left join, we get all the records from the left table along with only the matching records from the right table.

The other options don't accurately capture the behavior of a left join. For instance, retaining only matches from both tables does not reflect the nature of a left join, as that describes an inner join. Similarly, stating that all records from both tables are included doesn't represent the key feature of a left join, which emphasizes the preservation of all records from the left table only. Finally, stating that unmatched records from the left are discarded contradicts the fundamental principle of a left join, which is explicitly designed