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!
Example:; transfers transfer_amount from x's account to y's account
; Supposes x&y both accounts exist
TRANSACTION (x, y, transfer_amount)
Start transaction
IF X AND Y exist then
READ x.balance
IF x.balance > transfer_amount THEN
x.balance = x.balance - transfer_amount
READ y.balance
y.balance = y.balance + transfer_amount
COMMIT
ELSE DISPLAY ("BALANCE IN X NOT OK") ROLLBACK
ELSE DISPLAY ("ACCOUNT X OR Y DOES NOT EXIST") End_transaction
Please note the use of 2 keywords here COMMIT and ROLLBACK. Commit makes sure that all the modifications made by transactions are made permanent. ROLLBACK ends the transactions and discards any change made by the transaction. Transactions have definite desirable properties. Let us see into those properties of a transaction.
Answer SQL Queries to extract data from data tables and questions on mapping conceptual data models into relational data model.
how map binary relation one to one
Question : (a) Explain with the help of appropriate examples the difference between ‘Data' and ‘Information'. (b) A digital image is an array of pixels, where each pixel h
Define the Query optimisation The query parser commonly generates a standard initial tree to correspond to an SQL query, with no doing any optimization. Such type of a canonica
Consider the following relational scheme: R (a,b,c,d,e,f) and its corresponding set of FDs {d→ a, be → c, ac → e, b → f, f → d, a → c}. a. Is the following decomposition i) non
Design a gennalization and specialization hierarchy for an automobile sales company
Explain five duties of Database Administrator? 1. DBA administers the three stages of the database and, in consultation along with the whole user community, sets up an defin
What are the Constituents of File? Also elaborates all the possible file operations? A file is organised logically as sequence of record. These records are mapped onto disk blo
Lack of Redundancy We have talked about the problems of repetition of information in a database. Such repetition should be stay away as much as possible. Let us state once again t
Question 1 Define OLTP? Explain the Differences between OLTP and Data Warehouse Question 2 What is Architecture? Explain various components involved in it Question
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd