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!
NULL Statement
The NULL statement clearly specifies in action; it does nothing other than to pass control to the next statement. It can, though, improve the readability. In a construct allowing the substitute actions, the NULL statements serve as a placeholder. It tells the readers that the related alternative has not been overlooked, but required that no action is necessary. In the following illustration, the NULL statement shows that no action is taken for the unnamed exceptions:EXCEPTIONWHEN ZERO_DIVIDE THENROLLBACK;WHEN VALUE_ERROR THENINSERT INTO errors VALUES...COMMIT;WHEN OTHERS THENNULL;END;Each of the clause in an IF statement should contain at least one executable statement. TheNULL statement is executable; therefore you can use it in clauses that correspond to the circumstances in which no action is taken. In the following illustration, the NULL statements emphasize that only top-rated employees get bonus:IF rating > 90 THENcompute_bonus(emp_id);ELSENULL;END IF;The NULL statement is also a handy way to create stubs when designing the applications from the top down. A stub is dummy subprogram that permits you to defer the definition of a procedure or function till you test and debug the main program. In the following illustration, the NULL statement meets the requirement that at least one statement should appear in the executable part of a subprogram:PROCEDURE debit_account (acct_id INTEGER, amount REAL) ISBEGINNULL;END debit_account;
Scope Rules You cannot declare an exception twice in the similar block. Though, you can, declare the similar exception in 2 different blocks. The Exceptions declared in a bloc
Declarations in SQL Your program stores values in the variables and constants. As the program executes, the value of the variables can change, but the values constants cannot.
Product-specific Packages The Oracle and different Oracle tools are supplied with the product-specific packages which help you to build the PL/SQL-based applications. For illus
Majority of Differences among 9i, 10G, 11G :- These are some combine feature which has differences among others. Automatic Workload Repository (AWR) Drop database' s
Parameter and Keyword Description: EXIT: An unconditional EXIT statement (i.e., one without a WHEN clause) exits the present loop instantly. The Execution resumes with th
ALTER TABLE bb_basketitem ADD CONSTRAINT bitems_qty_ck CHECK (quantity BEGIN INSERT INTO bb_basketitem VALUES (88,8,10.8,21,16,2,3); END; Brewbean’s wants to add a check
Declaring Subprograms You can declare subprograms in any PL/SQL subprogram, block, or package. But, you should declare subprograms at the end of the declarative part after a
Cursor Attributes The Cursors and cursor variables have 4 attributes which give you helpful information about the execution of a data manipulation statement. Syntax:
Using DEFAULT You can use the keyword DEFAULT rather than that of the assignment operator to initialize the variables. For e.g. the declaration blood_type CHAR := ’O’; it can b
GOTO Statement The GOTO statement branches to a label unconditionally. The label must be exclusive within its scope and should precede an executable statement or a PL/SQL block.
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