Cloudera HBase Certification Questions and Answers (Dumps and Practice Questions)

Question : In case of RegionServer crash..

1. Master splits the Hlog into a per-region log
2. Reassigns Regions to another RegionServer
3. Access Mostly Uused Products by 50000+ Subscribers
4. All 1,2 and 3 are correct
5. All 1,2 and 3 are wrong


Correct Answer : Get Lastest Questions and Answer :

In case of RegionServer Crash
MemStore is in memory and its data is lost

Recent changes would still be in MemStore
HLog is used to reapply the recent changes

Region StoreFiles (HFiles) are stored in HDFS

Master notices that Regions are not being served
Master splits the Hlog into a per-region log
Reassigns Regions to another RegionServer
RegionServer automatically applies the log





Question :

Which of the following are the file types in HBase

1. HLog
2. HFile
3. Access Mostly Uused Products by 50000+ Subscribers
4. Only 1,2 are correct
5. Only 1 and 3 are correct




Correct Answer : Get Lastest Questions and Answer :

HBase has two file types
HLog
- Used for the Write Ahead Log (WAL)
- Standard Hadoop SequenceFile
- Stores HLogKeys as well as actual data
- HLogKeys are used to replay not yet persisted data after a server crash
HFile
- Used for actual data storage





Question :

Select the correct statement for the RegionServer files


1. Files are handled by the HRegionServer
2. Files are divided up into smaller blocks when stored in HDFS
3. Access Mostly Uused Products by 50000+ Subscribers
4. 1 and 2 are correct
5. All 1 , 2 and 3 are correct




Correct Answer : Get Lastest Questions and Answer :

RegionServer Files
Files are handled by the HRegionServer
Files are divided up into smaller blocks when stored in HDFS
Block replication is handled by HDFS

Related Questions

---

Question : Given the following HBase code:

HTable customers = new HTable(hconf, "customers");
byte [] rowKey = Bytes.toBytes(65);
Put put = new Put(rowKey);
put.add("info".getBytes(), "FirstName".getBytes(), "Kimberly".getBytes());
put.add("info".getBytes(), "LastName".getBytes(), "Grant".getBytes());

What line of code adds this data to the table named "customers"?



1. put.insertRow(customers);
2. put.add(customers);
3. Access Mostly Uused Products by 50000+ Subscribers
4. customers.add(put);



Question : Given the following HBase code:
byte [] rowKey = Bytes.toBytes(65);
Get get = new Get(rowKey);
Result result = customers.get(get);

Which one of the following statements is true?



1. The result variable will contain all values from all column families for the row whose key is 65
2. The result variable in this example will always be null
3. Access Mostly Uused Products by 50000+ Subscribers
4. The result variable will not contain any values and can be used for retrieving the column values



Question : Given the following HBase code:

byte [] rowKey = Bytes.toBytes(65);
Get get = new Get(rowKey);
get.addFamily("info".getBytes());
Result result = customers.get(get);

Which one of the following statements is true?




1. The method call to addFamily does not compile
2. The result will contain all values from all column families for the row whose key is 65
3. Access Mostly Uused Products by 50000+ Subscribers
4. The result will contain all values from the "info" column qualifier for the row whose key is 65