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!
Defining REF CURSOR Types
To make cursor variables, you take 2 steps. At first, you define a REF CURSOR type, and then declare the cursor variables of that type. You can define the REF CURSOR types in any PL/SQL subprogram, block, or package using the syntax as shown:
TYPE ref_type_name IS REF CURSOR RETURN return_type;
Where ref_type_name is a type specifier used in the subsequent declarations of the cursor variables and return_type should present a record or a row in a database table. In the illustration below, you specify a return type that presents a row in the database table dept:
DECLARE
TYPE DeptCurTyp IS REF CURSOR RETURN dept%ROWTYPE;
REF CURSOR types can be weak (nonrestrictive) or strong (restrictive).
IS NULL Operator The IS NULL operator returns the Boolean value TRUE whenever its operand is null or FALSE if it is not null. The comparisons including the nulls always yield NU
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
Procedural Constraint Enforcement (Triggers) SQL has an alternative method of addressing database integrity, involving event-driven procedural code. The special procedures th
Raise_application_error - procedure of package DBMS_STANDARD , allows to issue an user_defined error messages by stored sub-program or database trigger.
Usefulness of Data Type In SQL, as in most computer languages, a type can be used for constraining the values that are permitted to be used for some purpose. In particular, i
Functions The function is a subprogram which can take parameters and be invoked. Normally, you can use a function to calculate a value. The function has 2 sections: the specifi
Updating by replacement Syntax: UPDATE ENROLMENT SET Name = 'Ann' WHERE StudentId = SID ('S1'); Note the use of SET, as already noted in connection with direct a
OPEN-FOR Statement The OPEN-FOR statements execute the multi-row query related with a cursor variable. It also allocates the resources used by the Oracle to process the query a
How Calls Are Resolved? The figure shows that how the PL/SQL compiler resolves the subprogram calls. When the compiler encounters the procedure or function call, it tries to di
Subprograms The PL/SQL has two types of subprograms known as the procedures and functions that can take parameters and be invoked. As the following example represents, a subp
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