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

Question : In which case Hbase should not be used ?


1. When you only append data to your dataset and read the whole data
2. When you need random read
3. When you need random write
4. When access pattern is well known



Correct Answer : 1
HBase is a good fit when
You need random write, random read, or both (but not neither)
You need to do many thousands of operations per second on multiple TB of data
Your access patterns are well-known and simple

HBase is not a good fit when
You only append to your dataset, and tend to read the whole thing
You primarily do ad-hoc analytics (ill-defined access patterns)
Your data easily fits on one beefy node





Question :

One technical architech designing a solution for storing huge data volume which is everyday generated by stock markets and its purpose
is only storing these data and reading it once for daily analysis and he comes to conclusion that, he will use HBase. So he took a right decision



1. Yes
2. No

Correct Answer : 2


Explanation: HBase is not good fit for just appending the data and reading it back as whole thing. In this case he should consider using HDFS file system only to
store the data and reading it back from the files as a whole.




Question :

Please select the correct answer for HBase ?


1. In HBase every row has a Row Key
2. All columns in HBase are belongs to a particular column family
3. A table can have one or more column families
4. Table cells are versioned
5. All of the above




Correct Answer : 5

HBase data models has following features
Tables are made of rows and columns
Every row has a row key (analogous to a primary key)

Rows are stored sorted by row key for fast lookups

All columns in HBase belong to a particular column family

A table may have one or more column families
Common to have a small number of column families
Column families should rarely change
A column family can have any number of columns

Table cells are versioned, uninterpreted arrays of bytes

Related Questions

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Question : Which staement is correct for versioning


1. The versions are sorted by their timestamp in ascending order
2. The versions are sorted by their timestamp in descending order
3. By default HBase maintains unlimited number of versions
4. Only 1 and 3 are correct
5. Only 2 and 3 are correct



Question : When get and scan operation is performed on the HBase, then by default it will return


1. Cell with largest value for version is returned
2. Cell with smallest value for version is returned
3. It return any random value from the all versions
4. None of the above is correct



Question : To retrive the last three versions of the row, which operation needs to be performed




1. get.setMaxVersions(3);
2. get.setMaxVersions("three");
3. get.setAllVersions(3);
4. htable.get(get);
5. Bydefault it always return latest three versions only





Question : Which statement is correct regarding the Put operation for inserting the data

1. It doen not replace existing Cell
2. Always creates a new versions of the Cell
3. Default version is the Server's currentTimeMillis
4. Versions can be specified on a per-column basis
5. All of the above




Question : Which of the code segment can be used to explicitely set the version time as


1. put.add(Bytes.toBytes("cf"), Bytes.toBytes("attr1"), 777, Bytes.toBytes(data));
2. put.add(Bytes.toBytes("cf"), Bytes.toBytes("attr1"), "777", Bytes.toBytes(data));
3. put.add(Bytes.toBytes("cf"), Bytes.toBytes("attr1"), Bytes.toBytes(data), "777");
4. None of the above is correct


Question : Which statement is true regarding the data delete in HBase
table


1. Deleted data is not immediately removed
2. Delete creates a tombstone marker
3. Tombstones masks the deleted values
4. Data is removed at major compaction
5. All of the above