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!
Transaction Control
The Oracle is transaction oriented; that is, Oracle uses the transactions to make sure the data integrity. The transaction is a sequence of SQL data manipulation statements that does a logical unit of work. For illustration, the two UPDATE statements might credit one bank account and debit another.
At the same time, the Oracle makes permanent or undoes all the database changes made by a transaction. If your program fails in the middle of the transaction, the Oracle detects the error and rolls back the transaction. Therefore, the database is restored to its previous state automatically.
You use the ROLLBACK, COMMIT, SAVEPOINT, & SET TRANSACTION commands to control the transactions. The COMMIT makes everlasting and any database changes made during the present transaction. The ROLLBACK ends the present transaction and undoes any changes made as the transaction began. The SAVEPOINT marks the present point in the processing of a transaction. Used with the ROLLBACK, SAVEPOINT undoes part of a transaction. The SET TRANSACTION sets the transaction properties like the read/write access and isolation level.
Processing Transactions This part describes how to do the transaction processing. You learn the fundamental techniques that safeguard the consistency of your database, involvin
Effects of NULL for UNIQUE Specification When a UNIQUE specification u for base table t includes a column c that is not subject to a NOT NULL constraint, the appearance of sev
Many of the reports generated from the system calculate the total dollars in purchases for a shopper. Complete the following steps to create a function named TOT_PURCH_SF that acce
Keyword & Parameter Description: boolean_expression: This is an expression which yields the Boolean value that is TRUE, FALSE, & NULL. character_expression: This
Disjunction (OR, ∨) Again we have nine rows instead of just four and again, when unknown is not involved, the rows are as for 2VL. Also, when anything is paired with true, t
Creating a Table Syantax: CREATE TABLE ENROLMENT (StudentId SID, Name VARCHAR (30) NOT NULL, CourseId CID, PRIMARY KEY (StudentId, CourseId)) ; Explan
Creating and Destroying Base Tables: Example shows an SQL command to create the base table counterpart of the ENROLMENT variable Example Creating a base table. CREATE T
Use Object Types and Collections The Collection types and object types increase your efficiency by allowing for the realistic data modeling. The Complex real-world entities an
1- You can check attribute names from each table in DBF11 by running for example: desc dbf11.Member; desc dbf11.Agent; desc dbf11.Producer; Because some attribute names in
Using PRIOR and NEXT The PRIOR(n) returns the index number that precede index n in a collection. The NEXT(n) returns the index number which succeed the index n. If n has no pr
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