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:
List any two disadvantages of a database system ? The disadvantages of database system are: • Database systems are difficult, complex, and time-consuming to design. • Substanti
Describe Interfaces for the DBA? Interfaces for the DBA - Most database systems holds privileged commands which could be used only through the DBA's staff. These involves com
Importance Of File Organisation In Database To execute a database efficiently, there are various design tradeoffs needed. One of the most vital ones is the file Organisation. F
Question 1 Suppose the employee employee id, name, designation, salary, attendance and address of any employee has to be stored in a database. You can store these data in a sequen
Compare three clustering algorithms in Weka. For this comparison, you will need to use at least two different datasets. Run the algorithms on the datasets, and use the visual
Explain degree of relation? Degree of a Relation - The degree or arity of a relation is the number of attributes n of its relation schema.
Define the terms i) Entity type ii) Entity set Entity type: An entity type describes a collection of entities that have the similar attributes. Entity set: The set of all en
Why do you go for sorting your query results? SQL SELECT command to fetch data from MySQL table. Whenever you select rows, the MySQL server is free to return them in any order
Define check point and its impact on data base recovery. Ans: There could be hundreds of transactions handled per minute, in a large on-line database system.
A constraint named less_than_20 was defined on the field date_of_birth of table student. Delete this constraint. ALTER TABLE student DROP CONSTRAINT less_than_20;
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