Given the following table schemas: TableA: id values 1, 1, 2, 3, 4 TableB: id values 1, 2, 2, 4 What are the results of an inner join, left join, right join, and full outer join on the id column?

With the provided data:

TableA rows: (1), (1), (2), (3), (4)

TableB rows: (1), (2), (2), (4)

• Inner Join on id:

• id=1: 2 rows from A × 1 row from B = 2 rows
• id=2: 1 row from A × 2 rows from B = 2 rows
• id=4: 1 row from A × 1 row from B = 1 row

Total = 5 rows.

• Left Join (A left B):

• id=1: 2 rows (matches)
• id=2: 1 row (match)
• id=3: 1 row (no match → NULL for B)
• id=4: 1 row (match)

Total = 5 rows.

• Right Join (A right B):

• id=1: 1 row (match)
• id=2: 2 rows (matches)
• id=4: 1 row (match)

Total = 4 rows.

• Full Outer Join:

Combine all unique ids: 1, 2, 3, 4.

• id=1: 2 rows from A × 1 from B = 2 rows
• id=2: 1 from A × 2 from B = 2 rows
• id=3: 1 from A × 0 from B = 1 row (NULL for B)
• id=4: 1 from A × 1 from B = 1 row

Total = 6 rows.

These counts illustrate how duplicates and missing matches affect each join type.