Sorting Results

1. Sorting by Single Column

SELECT * FROM orders ORDER BY placed_at;

Default	Behavior
Direction	ASC
NULLs	NULLS LAST for ASC, NULLS FIRST for DESC

SELECT * FROM orders ORDER BY customer_id, placed_at DESC;

SELECT * FROM customers ORDER BY full_name ASC;

SELECT * FROM orders ORDER BY total_cents DESC;

SELECT * FROM customers ORDER BY last_seen DESC NULLS LAST;

Clause	Effect
NULLS FIRST	NULLs at top
NULLS LAST	NULLs at bottom

SELECT * FROM customers ORDER BY length(full_name), full_name;

SELECT id, total_cents/100.0 AS dollars FROM orders ORDER BY dollars DESC;

SELECT id, full_name, created_at FROM customers ORDER BY 3 DESC;

Note: Position-based ORDER BY is fragile; refactoring the SELECT list silently changes order. Prefer aliases.

SELECT * FROM customers ORDER BY full_name COLLATE "C";
SELECT * FROM products ORDER BY name COLLATE "en-US-x-icu";

Collation	Behavior
"C" / "POSIX"	Byte order (fastest, predictable)
ICU collations	Locale-aware, language-correct

SELECT * FROM orders ORDER BY total_cents DESC LIMIT 10;

Note: Add a matching multi-column index for ORDER BY + LIMIT queries to enable top-N index scans.