[CASSANDRA-13138] SASI tries to fetch an extra page when resultset size is same size as page size

• Type: Bug
• Status: Open
• Priority: Normal
• Resolution: Unresolved
• Component/s: Feature/SASI
• Severity: Normal
• Assignee: Alex Petrov
• Reporter: Alex Petrov

Authors

Alex Petrov

• Created: 20/Jan/17 11:31
• Updated: 16/Apr/19 09:30

Description

For example, in a dataset that would return 10 rows, SASI would try (and return an empty page) to fetch the next page, while filtering and 2i will return results correctly:

 pk | ck1 | ck2 | reg1 | reg2 | reg3
----+-----+-----+------+------+------
  6 |   5 |   5 |    5 |    5 |   10
  7 |   5 |   5 |    5 |    5 |   10
  9 |   5 |   5 |    5 |    5 |   10
  4 |   5 |   5 |    5 |    5 |   10
  3 |   5 |   5 |    5 |    5 |   10
  5 |   5 |   5 |    5 |    5 |   10
  0 |   5 |   5 |    5 |    5 |   10
  8 |   5 |   5 |    5 |    5 |   10
  2 |   5 |   5 |    5 |    5 |   10
  1 |   5 |   5 |    5 |    5 |   10

---MORE---
(10 rows)

(that -MORE- shouldn't have been there)

This might be an inherent limitation, although even if it is we can opt out for fetching limit+1 if the data limits aren't exhausted. Although it seems that there should be a solution for it.