Which statement about table joins in SQL is true?
A) Self-joins usually do not include WHERE or ORDER BY clauses.
B) You cannot perform a self-join on a table's primary key column.
C) Joins must be performed between at least two different tables.
D) SQL has no problem treating one table with two aliases as two tables.

Question

Quizplus · Accepted Answer

Self-joins can include WHERE or ORDER BY clauses, and you can perform a self-join on a table's primary key column. Joins do not have to be between two different tables; a table can be joined with itself using aliases, which SQL treats as if they were two separate tables. This is why option D is correct.

Which Statement About Table Joins in SQL Is True