3 ms·
No, they were stable all right, once the writes had settled down. The trouble is that sometimes it would write rows with an ascending ID sequence like 1 1,
by JulianMorrison 13y ago
No, they were stable all right, once the writes had settled down. The trouble is that sometimes it would write rows with an ascending ID sequence like
1
1,2
1,2,4
1,2,3,4
…and a read transaction that captured "1,2,4" would try reading the next ID > 4 and never see 3.
Evidently it allocated the ID and space for row 3 before writing it and exposing it to the other transactions. And sometimes that turned into a race condition.
- lukaseder 13y agoAha, I get it now. Yes, that's a little awkward. Although, 3 would re-appear when going back again but that might be even more confusing. But with OFFSET, you'd just have (frequently) shifting windows, right?
- JulianMorrison 13y agoI was trying to stream the table entries into a "tallying" type process. And of course it came out with the wrong numbers. Frustrating. I finally replaced the whole "chaser" process with a repeated full table scan with SQL aggregate functions. Wildly inefficient, but reliable.