cassandra-3.0

问题 After reading about the different load balancing policies available(https://datastax.github.io/cpp-driver/topics/configuration/), it seems to me that for best performance,particularly in multi data-center cluster, token-aware and latency-aware policy should be used together('Performance Tips' section of the above mentioned article). As per my understanding(assuming replication factor > 1), when we'll use both of these policies together, then the client will calculate the hash of the primary

问题 After reading about the different load balancing policies available(https://datastax.github.io/cpp-driver/topics/configuration/), it seems to me that for best performance,particularly in multi data-center cluster, token-aware and latency-aware policy should be used together('Performance Tips' section of the above mentioned article). As per my understanding(assuming replication factor > 1), when we'll use both of these policies together, then the client will calculate the hash of the primary

问题 I have writeen code like belo but getting error as below:- InvalidRequest: Error from server: code=2200 [Invalid query] message="Java source compilation failed: Line 1: java.util.String cannot be resolved to a type Line 1: Syntax error on token "Date", @ expected Line 4: SimpleDateFormat cannot be resolved to a type CREATE FUNCTION saumya.text2dt ( input text ) RETURNS NULL ON NULL INPUT RETURNS timestamp LANGUAGE java AS $$ java.text.ParseException java.text.SimpleDateFormat java.util.Date

问题 I have a cluster of cassandra (v3.11.4) with 14 nodes and I wanna to add a new node. The machine has 256GB memory and I set heap size (max and min) to 64GB . But I cannot add a new node due to memory error! What is the exact problem and What I need to do? The last line of logs are as follows: INFO [CompactionExecutor:1153] 2020-06-11 10:51:09,719 NoSpamLogger.java:91 - Maximum memory usage reached (20971520000), cannot allocate chunk of 1048576 INFO [Service Thread] 2020-06-11 10:51:10,339

来源： https://stackoverflow.com/questions/52971763/how-to-create-mapstring-class-and-create-its-object-dynamically-in-scala

来源： https://stackoverflow.com/questions/52971763/how-to-create-mapstring-class-and-create-its-object-dynamically-in-scala

来源： https://stackoverflow.com/questions/64153341/how-do-i-sort-data-by-the-last-update-date-in-cassandra

来源： https://stackoverflow.com/questions/63212586/cassandra-joinwithcassandratable-is-not-working-in-cassandra-cluster-but-working

问题 I am running nodetool repair -pr -full my_ks my_tbl in our Cassandra cluster(has two DCs). It sometimes hangs with below debug logs. It works after restarting the Cassandra process. Any hints on the root cause of this issue? DEBUG [GossipStage:1] 2020-07-13 14:04:22,818 FailureDetector.java:456 - Ignoring interval time of 2571566434 for /10.22.38.223 DEBUG [GossipStage:1] 2020-07-13 14:04:22,818 FailureDetector.java:456 - Ignoring interval time of 2495429260 for /10.22.38.26 DEBUG

问题 I am implementing a feature which requires looking up Cassandra by a list of primary keys. Below is an example data where id is primary key mytable id column1 1 423 2 542 3 678 4 45534 5 435634 6 2435 7 678 8 4564 9 546 Most of my queries a lookup by id, but for some special cases I would like to get data for a list of ids. The way I am currently doing is a follows: public Object fetchFromCassandraForId(int id); int ids[] = {1, 3, 5, 7, 9}; List<Object> results; for(int id: ids) { results.add