Answer
HASH indexes support equality lookups and are used in MEMORY tables. B-Tree indexes support ranges, sorting, and prefix lookups.
Quick Answer
B-Tree index: sorted structure, supports range queries, ORDER BY, BETWEEN, prefix LIKE - versatile. HASH index: maps keys to hash buckets, O(1) exact lookup, no range queries, no sorting, no prefix matching. InnoDB only supports B-Tree (it simulates hash with adaptive hash index in memory automatically). MEMORY engine supports explicit HASH indexes. For most use cases, B-Tree is the right choice.
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SugharaIQ Editorial Team
Verified Answer
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Source: SugharaIQ