Optimizing single-table queries
Consider all possible plans
Combine index scans
The essential difference between Index Scan and Bitmap Index Scan
| Index Scan |
Bitmap Index Scan |
| read page 123 |
[123] |
| read page 128 |
[123, 128] |
| read page 207 |
[123, 128, 207] |
| read page 123 |
[123, 128, 207] |
| read page 79 |
[79, 123, 128, 207] |
| read page 124 |
[79, 123, 124, 128, 207] |
|
Read pages 79, 123, 124, 128, 207, in order |
|