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PreparedStatement preparedStatement = session.prepare("insert into test2test.user (id, name) values (?, ?)");
PreparedStatement preparedStatement2 = session.prepare("update test2test.user set id='id_updated-1' where name=?");
PreparedStatement preparedStatement3 = session.prepare("update test2test.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")); |
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| Code Block |
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Caused by: com.datastax.driver.core.exceptions.WriteTimeoutException: Cassandra timeout during write query at consistency ONEQUORUM (12 replica were required but only 01 acknowledged the write) |
Observation
The data got inserted into user table and got updated as above batch execution
...
.
The WriteTimeoutException.getWriteType() == BATCH, ensures data is inserted into the table
Approach
To handle above WriteTimeoutException we can use BatchStatement.Type
| Code Block |
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BatchStatement batchStatement = new BatchStatement(BatchStatement.Type.UNLOGGEDLOGGED); |
There is 3 different types are present
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BATCH_LOG
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BATCH
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Batch type of LOGGED, guarantees atomic insertion of data, and WriteTimeoutException.getWriteType() == BATCH, eventually written to the appropriate replicas and the developer doesn't have to do anything.
Thus, the above two checks handles partial write.