Re: Cassandra Possible read/write race condition in LOCAL_ONE?
If you use LOCAL_ONE for write and read and you have RF>1, it means both operations could go to different replicas that does not have the data yet. Try to use LOCAL_QUORUM instead, as usual check your clocks as well. From: Jeff Jirsa Reply-To: "user@cassandra.apache.org" Date: Thursday 28 March 2019 at 23:29 To: cassandra Subject: Re: Cassandra Possible read/write race condition in LOCAL_ONE? Yes it can race; if you don't want to race, you'd want to use SERIAL or LOCAL_SERIAL. On Thu, Mar 28, 2019 at 3:04 PM Richard Xin wrote: Hi, Our Cassandra Consistency level is currently set to LOCAL_ONE, we have script doing followings 1) insert one record into table_A 2) select last_inserted_record from table_A and do something ... step #1 & 2 are running sequentially without pause, and I assume 1 & 2 suppose to run in same DC we are facing sporadic issues that step #2 didnt get inserted data by #1. is it possible to have a race condition when LOCAL_ONE that #2 might not get inserted data on step #1? Thanks in advance! Richard
Re: Cassandra Possible read/write race condition in LOCAL_ONE?
I'm reading the OP as doing this from a single server, if that's the case QUORUM / LOCAL_QUORUM will work. On Thu, Mar 28, 2019 at 3:29 PM Jeff Jirsa wrote: > > Yes it can race; if you don't want to race, you'd want to use SERIAL or > LOCAL_SERIAL. > > On Thu, Mar 28, 2019 at 3:04 PM Richard Xin > wrote: >> >> Hi, >> Our Cassandra Consistency level is currently set to LOCAL_ONE, we have >> script doing followings >> 1) insert one record into table_A >> 2) select last_inserted_record from table_A and do something ... >> >> step #1 & 2 are running sequentially without pause, and I assume 1 & 2 >> suppose to run in same DC >> >> we are facing sporadic issues that step #2 didnt get inserted data by #1. >> is it possible to have a race condition when LOCAL_ONE that #2 might not get >> inserted data on step #1? >> >> Thanks in advance! >> Richard - To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org
Re: Cassandra Possible read/write race condition in LOCAL_ONE?
Yes it can race; if you don't want to race, you'd want to use SERIAL or LOCAL_SERIAL. On Thu, Mar 28, 2019 at 3:04 PM Richard Xin wrote: > Hi, > Our Cassandra Consistency level is currently set to LOCAL_ONE, we have > script doing followings > 1) insert one record into table_A > 2) select last_inserted_record from table_A and do something ... > > step #1 & 2 are running sequentially without pause, and I assume 1 & 2 > suppose to run in same DC > > we are facing sporadic issues that step #2 didnt get inserted data by #1. > is it possible to have a race condition when LOCAL_ONE that #2 might not > get inserted data on step #1? > > Thanks in advance! > Richard >
Cassandra Possible read/write race condition in LOCAL_ONE?
Hi, Our Cassandra Consistency level is currently set to LOCAL_ONE, we have script doing followings 1) insert one record into table_A 2) select last_inserted_record from table_A and do something ... step #1 & 2 are running sequentially without pause, and I assume 1 & 2 suppose to run in same DC we are facing sporadic issues that step #2 didnt get inserted data by #1.is it possible to have a race condition when LOCAL_ONE that #2 might not get inserted data on step #1? Thanks in advance!Richard
