> Cassandra is used in a message process system. > The table will be created at a fixed time each day.
Make sure you're keeping the total number of tables which exist at any given time to a reasonable limit. There is a fixed memory cost for each table, and if you have too many tables you will produce memory pressure in Cassandra. On Mon, Mar 16, 2015 at 1:28 AM, 鄢来琼 <laiqiong....@gtafe.com> wrote: > Cassandra is used in a message process system. > > The table will be created at a fixed time each day. > > We want the table can be created before the message arrived. > > So I want to guarantee table is created in all the nodes. > > > > Peter > > > > *发件人:* 鄢来琼 > *发送时间:* 2015年3月16日 15:14 > *收件人:* user@cassandra.apache.org > *主题:* Re: Is Table created in all the nodes if the default consistency > level used > > > > Hi Daemeon, > > > > Yes, I use “NetworkTopologyStrategy” strategy for “Table_test”, > > but “System keyspace” is Cassandra internal keyspace, its strategy is > localStrategy. > > So my question is how to guarantee “Table_test” is created in all the > nodes before any R/W opertions? > > > > Thanks. > > > > Peter > > > > > > *发件人:* daemeon reiydelle [mailto:daeme...@gmail.com] > *发送时间:* 2015年3月16日 14:35 > *收件人:* user@cassandra.apache.org > *主题:* Re: Is Table created in all the nodes if the default consistency > level used > > > > If you want to guarantee that the data is written to all nodes before the > code returns, then yes you have to use "consistency all". Otherwise there > is a small risk of outdated data being served if a node goes offline longer > than hints timeouts. > > Somewhat looser options that can assure multiple copies are written, as > you probably know, are quorum or a hard coded value. This applies to a > typical installation with a substantial number of nodes of course, not a > small 2-3 node cluster. > > I am curious why localStrategy when you have such concerns about data > consistency that you want to assure all nodes get data written. Can you > elaborate on your use case? > > > > > > > > > > > > * ....... “Life should not be a journey to the grave with the intention of > arriving safely in a pretty and well preserved body, but rather to skid in > broadside in a cloud of smoke, thoroughly used up, totally worn out, and > loudly proclaiming “Wow! What a Ride!” - Hunter Thompson Daemeon C.M. > Reiydelle USA (+1) 415.501.0198 <%28%2B1%29%20415.501.0198> London (+44) > (0) 20 8144 9872 <%28%2B44%29%20%280%29%2020%208144%209872>* > > > > On Sun, Mar 15, 2015 at 8:11 PM, 鄢来琼 <laiqiong....@gtafe.com> wrote: > > Could you tell me whether the meta data of the new table are build in all > the nodes after execute the following statement. > > > > *cassandra_session.execute_async(* > > *“““**CREATE TABLE Table_test(* > > * ID uuid,* > > * Time timestamp,* > > * Value double,* > > * Date timestamp,* > > * PRIMARY KEY ((ID,Date), Time)* > > *) WITH COMPACT STORAGE;* > > *”””* > > *)* > > > > As I know, the system keyspace is used to store the meta data, but the > strategy is localStrategy, which only store meta data of local node. > > So I want to know whether table is created in all the nodes, should I add > consistency_level setting to the above statement to make sure > > “create table” will be executed in all the nodes? > > Thanks. > > > > Peter > > > > >
