Re: Necessary consistency level for LWT writes

2019-05-23 Thread Craig Pastro
Dear Hiro, Thank you! Yes, this is exactly my understanding. Is this explicitly written down anywhere or can any expert confirm? I suppose I should read the code but its a little intimidating. Best wishes, Craig On Fri, May 24, 2019 at 11:11 AM Hiroyuki Yamada wrote: > Hi Craig, > > Now I

Re: Necessary consistency level for LWT writes

2019-05-23 Thread Hiroyuki Yamada
Hi Craig, Now I probably understand what the python doc is saying. As long as `serial_consistency_level` is set to SERIAL for paxos phase and `consistency_level` is set to SERIAL for the later read, conflicts in paxos table can be properly detected, so `consistency_level` for commit phase can be

Re: Necessary consistency level for LWT writes

2019-05-23 Thread Craig Pastro
Dear Hiro, Thank you for your response! Hmm, my understanding is slightly different I think. Please let me try to explain one situation and let me know what you think. 1. Do a LWT write with serial_consistency = SERIAL (default) and consistency = ONE. 2. LWT starts its Paxos phase and has

Re: Necessary consistency level for LWT writes

2019-05-23 Thread Hiroyuki Yamada
Hi Craig, I'm not 100 % sure about some corner cases, but I'm sure that LWT should be used with the following consistency levels usually. LWT write: serial_consistency_level: SERIAL consistency_level: QUORUM LWT read: consistency_level: SERIAL (It's a bit weird and mis-leading as a design that

schema for testing that has a lot of edge cases

2019-05-23 Thread Carl Mueller
Does anyone have any schema / schema generation that can be used for general testing that has lots of complicated aspects and data? For example, it has a bunch of different rk/ck variations, column data types, altered /added columns and data (which can impact sstables and compaction),

Re: Select in allow filtering stalls whole cluster. How to prevent such behavior?

2019-05-23 Thread Attila Wind
Hi again, so remaining with a) for a second... "Why am I using ALLOW FILTERING in the first place?" Fully agreed! To put it this way: as I reviewer I never want to see string occurence "allow filtering" in any selects done by a production code. I clearly consider it as an indicator of a wrong

Re: Select in allow filtering stalls whole cluster. How to prevent such behavior?

2019-05-23 Thread shalom sagges
a) Interesting... But only in case you do not provide partitioning key right? (so IN() is for partitioning key?) I think you should ask yourself a different question. Why am I using ALLOW FILTERING in the first place? What happens if I remove it from the query? I prefer to denormalize the data to

Necessary consistency level for LWT writes

2019-05-23 Thread Craig Pastro
Hello! I am trying to understand the consistency level (not serial consistency) required for LWTs. Basically what I am trying to understand is that if a consistency level of ONE is enough for a LWT write operation if I do my read with a consistency level of SERIAL? It would seem so based on what