...
For testing different scenarios keyspace and table created
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CREATE KEYSPACE test WITH replication = {'class':'SimpleStrategy', 'replication_factor' : 2};
CREATE TABLE user(name text, id text, PRIMARY KEY (name)); |
In java
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PreparedStatement preparedStatement = session.prepare("insert into test2.user (id, name) values (?, ?)");
PreparedStatement preparedStatement2 = session.prepare("update test2.user set id='id_updated-1' where name=?");
PreparedStatement preparedStatement3 = session.prepare("update test2.user set id='id_updated-2' where name=?");
int i = 1;
while(i <= 1000) {
batchStatement.add(preparedStatement.bind("id_"+i, "user-" + i));
++i;
}
batchStatement.add(preparedStatement2.bind("user-1"));
batchStatement.add(preparedStatement3.bind("user-2")); |
...
The above query will throw exception
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Caused by: com.datastax.driver.core.exceptions.WriteTimeoutException: Cassandra timeout during write query at consistency ONE (1 replica were required but only 0 acknowledged the write) |
Observation
The 1000 row data got inserted into user table and got updated also as above batch execution
Suggestion
To handle above WriteTimeoutException we can use BatchStatement.Type
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BatchStatement batchStatement = new BatchStatement(BatchStatement.Type.UNLOGGED); |
There is 3 different types are present
BATCH_LOGBATCHUNLOGGED_BATCH
In cassandra doc it specifies that to increase the performance UNLOGGED_BATCH type should get use.