hard20 pts · first answer countsindexing
Physical order and index cost
Two tables have the same rows and the same index on created_at. In table A rows were inserted in time order; in table B they were loaded in random order. A range query on created_at uses an Index Scan on A but a Bitmap or Seq Scan on B. Why?
Discussion 0
Join free to post in the discussion.
Related questions
- When a B-tree index helpsDatabase Administrator
- Index on a yes/no columnDatabase Administrator
- How InnoDB stores table rowsDatabase Administrator
- What an InnoDB secondary index points toDatabase Administrator
- LIKE with a leading %Database Administrator
- What a hash index supportsDatabase Administrator
- Cost of extra indexes on insertsDatabase Administrator
- EXPLAIN versus EXPLAIN ANALYZEDatabase Administrator