Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
What is a transaction?
The Transaction is a unit of data processing. For instance, many of the transactions at a bank may be withdrawal or deposit of money; transfer of money from A's account to B's account etc. A transaction would include manipulation of one or more data values in a database. Therefore, it may need reading and writing of database value. For instance, the withdrawal transactions can be written in pseudo code as:
Example:
; Suppose that we are doing this transaction for person
; whose account number is X.
TRANSACTION WITHDRAWAL (withdrawal_amount)
start transaction
IF X exist then
READ X.balance
IF X.balance > withdrawal_amount THEN
SUBTRACT withdrawal_amount
WRITE X.balance
COMMIT
ELSE
DISPLAY "TRANSACTION CANNOT BE PROCESSED"
ELSE DISPLAY "ACCOUNT X DOES NOT EXIST"
End transaction;
Another same example may be transmitting of money from Account no x to account number y. This transaction may be written as:
Explain the shadow paging recovery technique. Ans: Shadow paging is a method used to acquire atomic and durable transactions, and provides the capability to manipulate pages i
Problem 1. Create a PL/SQL program to insert data into student table and display the details of the student having Reg.No 1010 Writing a PL/SQL program to Insert data
Define functional and multivalued dependencies. Ans: A functional dependency is a assets of the semantics of the attributes in a relation. The semantics point out how at
Increased parallelism : Since the replicated date has several copies a query can be distributed or can be answered from the smallest loaded site. Also, with more replicas you have
Find a 3NF decomposition of the following relation scheme: University (Faculty, Dean, Department, Chair, Professor, Rank, Student}. The University relation satisfies the following
Why are cursors necessary in embedded SQL? A cursor is an object used to store the output of a query for row-by-row processing through the application programs. SQL statements
Define multivalued dependency and 4NF. Ans: Multivalued Dependency - Assume R be a relation schema and let α ⊆ R and β ⊆ R. The multivalued dependency α →→β holds o
Question: One of the tasks a database management system must perform is to ensure that the data is still intact in the face of software and hardware failure. This task is known
State about the Tables- DBMS Data is stored in columns and rows (much like a spreadsheet -main difference is how data is organised). Every row in a table is known as a record
What is entity in DBMS? Entity: A DBMS entity is either a thing in the modelled world or a drawing element in an ERD.
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd