Q: Multi-column sort with different directions

Level sorts A before B (ascending). Within level A, scores sort descending: Carol (500) before Alice (300). Within level B, scores sort descending: Dave (400) before Bob (200). Each sort key applies independently within the groups created by the keys before it.

Question 1

ORDER BY multiple columns

Accepted Answer

When sorting by multiple columns, the first column is the primary sort key. Within each dept group, rows are sorted by the second key. Eng comes before Sales alphabetically. Within Eng, Bob (90000) outranks Carol (80000) on DESC salary. Within Sales, Alice and Dave both earn 70000, so they are tied on salary - their relative order is database-defined, but both come after Eng.

Question 2

ORDER BY ascending

Accepted Answer

ORDER BY salary ASC sorts rows from lowest to highest salary. Bob (75000) comes first, Carol (82000) second, Alice (90000) last. ASC is the default direction and can be omitted - ORDER BY salary is equivalent.

Question 3

ORDER BY combined with WHERE

Accepted Answer

WHERE filters first - only rows where amount > 200 survive. That removes Alice's 200-dollar order and Carol's 150-dollar order. The remaining two rows are then sorted by amount DESC: 500 before 350. ORDER BY runs after WHERE in the logical query order.

Question 4

ORDER BY descending

Accepted Answer

ORDER BY price DESC sorts from highest to lowest. Gadget (25.00) is first, Doohick (15.00) second, Widget (10.00) last. DESC must be written explicitly - there is no default descending sort.

Question 5

Alphabetical sort

Accepted Answer

Sorting a text column alphabetically works the same as sorting numbers - ASC goes A to Z. Brazil < Denmark < France in alphabetical order. The database uses locale-aware collation rules, but for plain ASCII letters the result is standard alphabetical order.

Question 6

Multi-column sort with different directions

Accepted Answer

Level sorts A before B (ascending). Within level A, scores sort descending: Carol (500) before Alice (300). Within level B, scores sort descending: Dave (400) before Bob (200). Each sort key applies independently within the groups created by the keys before it.