Correct Answer: A spanning tree is a tree associated with a network All the nodes of the graph appear on the tree once A minimum spanning tree is a spanning tree organized so that the total edge weight between nodes is minimized
2. Classify the Hashing Functions based on the various methods by which the key value is found.
Correct Answer: The mapreduce framework contains most of the key architecture principles of cloud computing such as: - Scale: The framework is able to expand itself in direct proportion to the number of machines available - Reliable: The framework is able to compensate for a lost node and restart the task on a different node - Affordable: A user can start small and over time can add more hardware
Correct Answer: One can use simple conditions like >= and <=, or use between/and but the trick here is to know your exact data type - Sometimes date fields contain time and that is where the query can go wrong so it is recommended to use some date related functions to remove the time issue In SQL Server common function for accomplishing the task datediff () function - Interviewees also have to be aware of different time zones and server time zone -To increase query performance you may still want to use between however you should be aware of proper format you should use if not it might misbehave during filtering
7. Which TCP/IP port does SQL Server run on? How can it be changed?
Correct Answer: In a nutshell, a temp table is a temporary storage structure It means you can use a temp table to store data temporarily so you can manipulate and change it before it reaches its destination format In table_usergender column change ?male to female? and ?female to male? in one SQL statement UPDATE table_user SET gender = CASE gender WHEN ?male? THEN ?female? WHEN ?female? THEN ?male? ELSE gender END
Correct Answer: SQL JOIN allows access to records of other table based on the given conditions between two tables Ex: If we are provided with the department ID of each employee, then we can use the department ID of the employee table to merge with the department ID of the department table to access department names UNION operation allows addition of 2 similar data sets to create a resulting set that contains all the data from the source data sets Ex: If we are provided with 2 employee tables of the same structure, we can UNION them to create a singular result that will contain all employee from both the table
Correct Answer: The knowledge of Joins is a MUST for every interviewee Most SQL programmers have used inner join and outer join[left/right]; but the catch point here is to also mention cross join and self-join