projecting the literal 'hi' for table dept 'H -- hi hi hi hi hi hi 6 rows selected. dept_num concatenated with dept_name: DEPT_NUM||DEPT_NAM ------------------ 100Accounting 200Research 300Sales 400Operations 500Management 600Computer Sci 6 rows selected. what if I concatenate a literal ' - ' between dept_num and dept_name? DEPT_NUM||'-'||DEPT_N --------------------- 100 - Accounting 200 - Research 300 - Sales 400 - Operations 500 - Management 600 - Computer Sci 6 rows selected. how about adding a column alias: Departments --------------------- 100 - Accounting 200 - Research 300 - Sales 400 - Operations 500 - Management 600 - Computer Sci 6 rows selected. projecting department data in comma-separated/CSV format: DEPT_NUM||','||DEPT_NAME||','||DEPT_L ------------------------------------- 100, Accounting, New York 200, Research, Dallas 300, Sales, Chicago 400, Operations, Boston 500, Management, New York 600, Computer Sci, Arcata 6 rows selected. names of departments located in Chicago or Dallas: DEPT_NAME --------------- Research Sales adding a Computer Sci row to dept insert into dept * ERROR at line 1: ORA-00001: unique constraint (ST10.SYS_C00876465) violated project the locations and names of departments with employees (for each department, do any employees EXIST for that department?) DEPT_LOC DEPT_NAME --------------- --------------- New York Accounting Dallas Research Chicago Sales Boston Operations New York Management which departments have NO employees? DEPT_LOC DEPT_NAME --------------- --------------- Arcata Computer Sci OOPS, left off correlation condition with NOT EXISTS! (you might think it means all departments have employees, but Computer Sci department does not) (this will show no rows selected, even though Computer dept has no employees...) no rows selected OOPS, left off correlation condition with EXISTS! (you might think it means all departments have employees, but Computer Sci department does not) (this will also select Computer Sci dept, even though Computer Sci dept has no employees...) DEPT_LOC DEPT_NAME --------------- --------------- New York Accounting Dallas Research Chicago Sales Boston Operations New York Management Arcata Computer Sci 6 rows selected. OOOPS, this will not work, inner select has a join condition NOT a correlation condition (might THINK it says all departments have employees, but Computer Sci department does not) no rows selected using the HW 4 database, which client(s) have rented BOTH 'Gone with the Wind' and 'Star Wars'? Windy Starry Client(s) -------------------------------- Beta, Edie double-check: what movies has Edie Beta rented? MOVIE_TITLE ---------------------------------------- Star Wars Gone with the Wind Indiana Jones and the Temple of Doom