Indexes: a suitable lookup structure
An index is an additional lookup structure, not a report or timing promise. Composite key order matters. An ordinary index permits duplicates; UNIQUE adds a different rule. SELECT meaning stays the same; request ORDER BY for output order.
An index is an additional lookup structure, not a report or timing promise. Composite key order matters. An ordinary index permits duplicates; UNIQUE adds a different rule. SELECT meaning stays the same; request ORDER BY for output order.
- Indexes: a suitable lookup structure
- An index is an additional lookup structure, not a report or timing promise. Composite key order matters. An ordinary index permits duplicates; UNIQUE adds a different rule. SELECT meaning stays the same; request ORDER BY for output order.