Question

which results would show if the genre table left joined the track table? all genres, even those with no tracks in the track table only genres that don't have tracks in the track table only genres with tracks in the track table all rows from the track table, even those that have null genre id's

Answer 1

When a genre table is left joined with a track table, it shows all genres with their corresponding tracks; genres without any tracks are displayed with NULL values for the track-related columns.

Step-by-step explanation:

If a genre table is left joined with a track table, the result would show all genres, even those with no tracks in the track table. A left join is a type of SQL join that returns all records from the left table (genre), and the matched records from the right table (track). If there is no match, the result is NULL on the side of the table that lacks data. So, you would see all rows from the genre table, coupled with corresponding rows from the track table where possible. If there are genres that do not have any corresponding tracks, those rows will still appear, with NULL values in the columns that would typically contain data from the track table.