S, PL-SQL Programming

Assignment Help:
Question 1. Update stock levels when the order is cancelled

At times, customers make mistakes in submitting their orders and call to cancel the order. Brewbean’s wants to create a trigger that automatically updates the stock level of all products associated with a cancelled order and that updates the ORDERPLACED column of the BB_BASKET table to zero, reflecting that the order was not completed. Create a trigger named BB_ORDERCANCEL_TRG to accomplish this task by considering the following items:

1. The trigger needs to fire when a new status record is added to the BB_BASKETSTATUS table and when the IDSTAGE column is set to 4, which indicates order cancellation.
2. Each basket can contain multiple items in the BB_BASKETITEM table, so a CURSOR FOR loop may be an appropriate mechanism to update the stock level of each item.
3. Keep in mind that coffee can be ordered in half o whole pounds.
4. Use basket 6 for testing. Note that this basket contains two items.
a. Open or return to SQL Plus. Execute the following statement to test the trigger:

Insert into bb_basketstatus (idstatus, idbasket, idstage, tdstage) values (bb_status_seq.nextval, 6, 4, sysdate);

b. Execute queries to confirm that the basket order status and product stock levels have been appropriately modified by the trigger.
c. Be sure to run the following statement to disable this trigger so that it does not affect other products:

Alter trigger bb_ordcancel_trg disable;

Related Discussions:- S

Effects of null operator, Effects of NULL Operator As a general rule-b...

Effects of NULL Operator As a general rule-but not a universal one-if NULL is an argument to an invocation of a system-defined read-only operator, then NULL is the result of t

Keyword & parameter description - exceptions, Keyword & Parameter Descripti...

Keyword & Parameter Description: WHEN: This keyword introduces the exception handler. You can have many exceptions execute the similar sequence of the statements by follo

Long and long raw in pl/sql, LONG and LONG RAW You use the LONG datatyp...

LONG and LONG RAW You use the LONG datatype to store the variable-length character strings. The LONG datatype is such as the VARCHAR2 datatype, except that the maximum length o

Parameter and keyword description - %type attribute, Parameter and Keyword ...

Parameter and Keyword Description: collection_name: This keyword identifies the index-by table, nested table, or varray formerly declared within the present scope. cu

Deriving predicates from predicates in sql, Deriving Predicates from Predic...

Deriving Predicates from Predicates in SQL The corresponding section in the theory book describes how predicates can be derived from predicates using (a) the logical connectiv

Cursor attributes in dynamic sql - pl sql, Using Cursor Attributes: Ev...

Using Cursor Attributes: Every cursor has 4 attributes: %NOTFOUND, %FOUND, %ISOPEN, and %ROWCOUNT. If appended to the cursor name, they return the helpful information about

Using limit - collection method, Using LIMIT For nested tables, that h...

Using LIMIT For nested tables, that have no maximum size, the LIMIT returns NULL. For varrays, the LIMIT returns the maximum number of elements that a varray can have (that yo

Max and min operator in sql, MAX and MIN operator in SQL Example: ...

MAX and MIN operator in SQL Example: (SELECT MAX (Mark) FROM EXAM_MARK WHERE StudentId = 'S1') (SELECT MIN (Mark) FROM EXAM_MARK WHERE StudentId = 'S1') Example

Perform exception handling with user-defined errors, On occasion, some of B...

On occasion, some of Brewbean's customers mistakenly leave an item out of a basket already checked out, so they create a new basket containing the missing items. However, they requ

Use the pls_integer datatype - performance of application, Use the PLS_INTE...

Use the PLS_INTEGER Datatype When you require to declare an integer variable, use the datatype PLS_INTEGER that is the most efficient numeric type. That is as the PLS_INTEGER

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd