cassandra

问题 I would appreciate some help on how to stress a Cassandra instance running on EC2 from my local machine (using cassandra-stress util). Cluster on EC2: Five nodes running DSE 4.6. Local machine: cassandra-stress as included in Cassandra 2.1.2. After changing the Security Group the stress util invoked from my local machine is able to connect to the given instance on EC2. I allowed inbound TCP connections on Ports 9160 and 9042 from my local machine's IP. sh cassandra-stress write -node 54.xxx

问题 Is there any way to upgrade cassandra cql spec version from 3.1.1 to 3.1.4 without upgrading cassandra itself? We are using cassandra version 2.0.9 and haven't found any documentation related to this issue. 来源： https://stackoverflow.com/questions/26386341/upgrade-cassandra-cql-spec

问题 We use python spark cassandra driver V3.0.0. from datastax When try to load data by using dataframe, the where clause doesn't work. However the CQL itself does work in Datastax DevCenter. The code looks like this dataf = sqlc.read.format("org.apache.spark.sql.cassandra")\ .options(table="tran_history", keyspace="test")\ .load()\ .where("usr_id='abc' log_ts >= maxtimeuuid('2016-02-01 10:09:26-0800')")\ .collect() It seems the driver doesn't recognize method maxtimeuuid ------------------Below

问题 I am only doing inserts to cassandra. While inserting , not nulls are only inserted to avoid tombstones. But few records are inserted with TTL. But then doing select count(*) from table gives following errors - Read 76 live rows and 1324 tombstone cells for query SELECT * FROM xx.yy WHERE token(y) >= token(fc872571-1253-45a1-ada3-d6f5a96668e8) LIMIT 100 (see tombstone_warn_threshold) Do TTL inserts lead to tombstones in cassandra 3.7 ? How can the warning be mitigated ? There are no updates

问题 I tried with the data type blob . That's giving some Datastax exception. I tried the object itself, bytearray. Still no good: Caused by: com.datastax.driver.core.exceptions.InvalidQueryException: Invalid STRING constant ([B@547248ad) for user_object of type blob This is the failing INSERT: executeSting.append("INSERT INTO htadb.objecttable (object_id, bucket_name, object_key, link, user_status, user_object) ") .append("VALUES (") .append(objectId).append(",'") .append(bucketName).append("','"

问题 I asked a question on here a couple of days ago and got some really good answers, i'm thinking about doing a facebook style website with profiles, bio's, etc, and asked whether i should use mysql, the answers were to use Cassandra because its much better. I'm just asking is this what everyone would suggest, its just i know mysql fairly well and would it be a completely stupid move on my part to use mysql over Cassandra (which i hadnt even heard of until 2 days ago) thanks 回答1: Go for MySQL.

问题 I asked a question on here a couple of days ago and got some really good answers, i'm thinking about doing a facebook style website with profiles, bio's, etc, and asked whether i should use mysql, the answers were to use Cassandra because its much better. I'm just asking is this what everyone would suggest, its just i know mysql fairly well and would it be a completely stupid move on my part to use mysql over Cassandra (which i hadnt even heard of until 2 days ago) thanks 回答1: Go for MySQL.

问题 I would like to work with Cassandra from javascript web app using REST API. REST should support basic commands working with DB - create table, select/add/update/remove items. Will be perfect to have something similar to odata protocol. P.S. I'm looking for some library or component. Java is a most preferred. 回答1: Staash solution looks perfect for the task - https://github.com/Netflix/staash 回答2: You can use DataStax drivers. I used it via Scala but you can use Java, a Session object is a long

问题 I would like to work with Cassandra from javascript web app using REST API. REST should support basic commands working with DB - create table, select/add/update/remove items. Will be perfect to have something similar to odata protocol. P.S. I'm looking for some library or component. Java is a most preferred. 回答1: Staash solution looks perfect for the task - https://github.com/Netflix/staash 回答2: You can use DataStax drivers. I used it via Scala but you can use Java, a Session object is a long

问题 I'm working on Cassandra, trying to get to know how it works. Encountered something strange while using IN operator. Example: Table: CREATE TABLE test_time ( name text, age int, time timeuuid, "timestamp" timestamp, PRIMARY KEY ((name, age), time) ) I have inserted few dummy data. Used IN operator as follows: SELECT * from test_time where name="9" and age=81 and time IN (c7c88000-190e-11e4-8000-000000000000, c7c88000-190e-11e4-7000-000000000000); It worked properly. Then, added a column of