Datastax Cassandra Administrator Certification Questions and Answer (Pratice Questions and Dumps)

Question-: Which of the following statements are valid for COPY command in the CQL (Cassandra Qury Language).

A. This is a replacement for the DSBulk command.
B. When importing data using COPY command, it is fine to have each row different number of columns.
C. If the column data type is integer then empty value automatically inserted as zero.
D. You should import less than million records using this command.

Answer: D

Explanation: There are multiple ways to importing data in your Cassandra cluster, you should use each one as per the need. CQL COPY command is good for copying less than millions of rows. It is not at all replacement of the tool called “DSBulk� which can be used for copying the entire cluster data and supports billions of rows to be copied.

There is an alternate way for the programmer for using the INSERT command, that is good option when you want to insert less than 1000’s of records in the cluster.

Empty data can be copied but keep in mind these are replace with the NULL values and not with any other values. Similarly, number of columns in the file which you are using for importing the data should have same number of columns in each row.



Question-: Which of the following command you can use to dump the SSTable in JSON format?

A. SSDump
B. sstabledump
C. sstablejsondump
D. Importsstable

Answer: B

Explanation: You can use sstabledump command to dump the data in the JSON format for a particular SSTTable.



Question-: Which of the following command would help in loading the SSTable to Cassandra cluster?
A. CQL Copy command
B. sstabledump
C. DSBulk
D. sstableloader

Answer: D

Explanation: There are multiple ways of copying data to the Cassandra cluster. But every tool has a different purposes. In this question it is asked that you need to copy the SSTable, SSTable has data in a specific format which can be understood by the Cassandra storage engine. For that you have a command or tool called sstableloader. This tool can load the existing SSTable data into the existing Cassandra cluster.

Related Questions

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Question-: Suppose there are two Database tables in your Cassandra cluster, HE_VISIT and HE_SIGNUP. As you can see that HE_VISIT table has a high throughput, frequent write operations for this table. Which of the following statements are correct with regards to memtable flush for each table?
A. Table HE_VISIT’s memtable fills up rapidly and gets flushed frequently the table HE_SIGNUP.
B. Table HE_SIGNUP’s memtable fills up slowly and rarely gets flushed.
C. When commit log reaches to its maximum size then it forces HE_SIGNUP’s to flush.
D. If the commit log space and memtable space are same size than table HE_Signup’s memtable would flush every time table HE_VISIT is flushed.


Question-: Which of the following is shared across all the tables?
A. Memtable
B. SSTables
C. Commit logs
D. Both memtable and SSTable



Question-: You have been given below detail from the directory stored on one of the nodes in the Cassandra cluster.

data/hadoopexam/course_fee-a5g22x211gf422l7790c34ad987777d3d/xx-1-bti-Data.db
Can you please map the following?

A. HadoopExam
B. Course_FEE
C. BTI
D. XX

1. Keyspace Name
2. Table Name
3. Access Mostly Uused Products by 50000+ Subscribers
4. Version of the SSTable



Question-: Compaction is a process
A. Which deletes data from memtables
B. Which deletes data from SSTables
C. It merges the various SSTables
D. It deletes the Tombstone marked data



Question-: Which of the following is true for the leveled compaction strategy?
A. It is very IO intensive process.
B. It compacts many more SSTable at once then size tiered compaction
C. This is executed more frequently than size tiered compaction.
D. None of the above


Question-: In which scenario do you think leveled compactions is a good strategy?
A. When your table has high write.
B. when your table has very intensive read operations.
C. it does not matter; it is good for every situation other than time series data.
D. you should avoid this compaction strategy altogether.