Take FREE!! Online Mettl Mock Test to Crack TechM and Other Companies Written Exams.
Get Off-Campus Placement Jobs Info !!!
TCS NQT Technical and Managerial Round Interview Questions

Technical Interview Questions and Answers :: Sopra Steria

9.52K

Tot. Mock Test: 10


Total Qs: 138+

  •  Select All
  •  SQL
  •  Java
  •  C++
  •  Informatica
  •  C
  •  DBMS
  •  Data Structure
  •  HR Question in TR
    Answer:

    A relation schema R is in 3NF if it is in 2NF and for every FD X -> A either of the following is true
    > X is a Super-key of R.
    > A is a prime attribute of R.
    In other words, if every non prime attribute is non-transitively dependent on primary key.

    Please Login First :

    62 / 138

    What is BCNF (Boyce-Codd Normal Form)?
    Answer:

    A relation schema R is in BCNF if it is in 3NF and satisfies an additional constraint that for every FD X -> A, X must be a candidate key.

    Please Login First :
    Answer:

    A relation schema R is said to be in 4NF if for every Multivalued dependency X ->-> Y that holds over R, one of following is true
    > X is subset or equal to (or) XY = R.
    > X is a super key.

    Please Login First :
    Answer:

    A Relation schema R is said to be 5NF if for every join dependency {R1, R2, ..., Rn} that holds R, one the following is true
    > Ri = R for some i.
    > The join dependency is implied by the set of FD, over R in which the left side is key of R.

    Please Login First :

    65 / 138

    What is durability in DBMS?
    Answer:

    Once the DBMS informs the user that a transaction has successfully completed, its effects should persist even if the system crashes before all its changes are reflected on disk. This property is called durability.

    Please Login First :

    66 / 138

    What do you mean by Correlated subquery?
    Answer:

    Subqueries, or nested queries, are used to bring back a set of rows to be used by the parent query. Depending on how the subquery is written, it can be executed once for the parent query or it can be executed once for each row returned by the parent query. If the subquery is executed for each row of the parent, this is called a correlated subquery.
    A correlated subquery can be easily identified if it contains any references to the parent subquery columns in its WHERE clause. Columns from the subquery cannot be referenced anywhere else in the parent query. The following example demonstrates a non-correlated subquery.
    E.g. Select * From CUST Where '10/03/1990' IN (Select ODATE From ORDER Where CUST.CNUM = ORDER.CNUM)

    Please Login First :

    67 / 138

    What is join in DBMS and What are the different types of JOIN operations?
    Answer:

    No Discussion on this question yet!

    Please Login First :

    68 / 138

    major difference between RDBMS and DBMS?
    Answer:

    No Discussion on this question yet!

    Please Login First :

    69 / 138

    What is 2 NF? Give an example of 2NF?
    Answer:

    No Discussion on this question yet!

    Please Login First :

    70 / 138

    What is a transaction and ACID properties in DBMS?
    Answer:

    A transaction is a very small unit of a program and it may contain several lowlevel tasks. A transaction in a database system must maintain Atomicity, Consistency, Isolation, and Durability − commonly known as ACID properties − in order to ensure accuracy, completeness, and data integrity.




    • Atomicity − This property states that a transaction must be treated as an atomic unit, that is, either all of its operations are executed or none. There must be no state in a database where a transaction is left partially completed. States should be defined either before the execution of the transaction or after the execution/abortion/failure of the transaction.

    • Consistency − The database must remain in a consistent state after any transaction. No transaction should have any adverse effect on the data residing in the database. If the database was in a consistent state before the execution of a transaction, it must remain consistent after the execution of the transaction as well.

    • Durability − The database should be durable enough to hold all its latest updates even if the system fails or restarts. If a transaction updates a chunk of data in a database and commits, then the database will hold the modified data. If a transaction commits but the system fails before the data could be written on to the disk, then that data will be updated once the system springs back into action.

    • Isolation − In a database system where more than one transaction are being executed simultaneously and in parallel, the property of isolation states that all the transactions will be carried out and executed as if it is the only transaction in the system. No transaction will affect the existence of any other transaction.

    Please Login First :


Most Frequent Qs.