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!
Using the Collection Methods
The collection methods below help to generalize the code and make collections easier to use and also make your applications easier to maintain:
EXISTS
COUNT
LIMIT
FIRST and LAST
PRIOR and NEXT
EXTEND
TRIM
DELETE
A collection method is a built-in function or the process that operates on collections and is called using the dot notation. The syntax is as shown below:
collection_name.method_name[(parameters)]
The Collection methods can be called from the procedural statements but not from the SQL statements. The COUNT, EXISTS, LIMIT, FIRST, PRIOR, LAST, & NEXT are the functions, that appear as a part of an expression. And EXTEND, DELETE, and TRIM are the procedures that appear as a statement. Also, the EXISTS, TRIM, PRIOR, NEXT, EXTEND, and DELETE take parameters. Each parameter should be an integer expression. Only the EXISTS can be applied to automatically null collections. Whenever you apply another method to such type of collections, then the PL/SQL raises COLLECTION_IS_NULL.
Example of Foreign Key Constraint Example: Alternative formulation for 6.3 as a foreign key constraint ALTER TABLE EXAM_MARK ADD CONSTRAINT Must_be_enrolled_to_take_exam
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
Using FOR UPDATE If you declare a cursor which will be referenced in the CURRENT OF clause of an UPDATE or DELETE statement, you should use the FOR UPDATE clause to obtain an
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
Example of NOT EXISTS Operator - SQL Example is a translation into SQL of the corresponding example, which is included there merely to show that for any scalar comparison the
Restriction in SQL Syntax: SELECT DISTINCT StudentId FROM IS_CALLED WHERE Name = 'Boris' The WHERE clause operates on the result of the FROM clause in analogo
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
Oracle 11 G new features associated with this release:- Enhanced ILM - Information Lifecycle Management (ILM) has been around for the almost 10 years, but Oracle has made
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
Other monadic - SQL In 2VL there are just 4 (2 2 ) monadic operators, of which negation is really the only "useful" one. When a third truth value is introduced we have 27 (3 3
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