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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.
Parameter and Keyword Description: select_item: This select_item is a value returned by the SELECT statement, and then assigned to the equivalent variable or field in the
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Based on the EMPLOYEE table created in Assignment #1, write a PL/SQL anonymous block that accepts an employee ID from the user input and finds whether the employee ID is in the EMP
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Restriction and AND - SQL Restriction is available via the WHERE operator, and so it is in SQL. However, by Example showing how a certain simple restriction can be expressed u
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