You run the following SQL statement: SELECT a.lname, a.location, b.dname, b.hiredate FROM emp a, emp b WHERE a.empid=b.empid; Which options are correct? (Choose all that apply)

This is a self join because the emp table is joined to itself using two different aliases (a and b). A self join is used when a table needs to be compared with itself, such as finding relationships between rows in the same table. The WHERE clause a.empid=b.empid creates an equijoin condition (using equality), but the defining characteristic is that it's a self join. The statement is syntactically valid and will execute successfully, returning each employee's lname and location paired with their dname and hiredate from the same row.