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!
Declarations in SQLYour program stores values in the variables and constants. As the program executes, the value of the variables can change, but the values constants cannot. You can declare the variables and constants in the declarative part of any PL/SQL block, package, or subprogram. The Declarations allocate the storage space for a value, state its datatype, and name the storage location and hence, you can reference it. A couple of examples are shown below: birthday DATE;emp_count SMALLINT := 0;The first declaration names a variable of the type DATE. The second declaration names a variable of the type SMALLINT and uses the assignment operator to assign an initial value of zero to the variable. The example next show that the expression following the assignment operator can be arbitrarily complex and can refer to the earlier initialized variables: pi REAL := 3.14159;radius REAL := 1;area REAL := pi * radius**2; By default, the variables are initialized to NULL. So, these declarations are equal: birthday DATE;birthday DATE := NULL; In the declaration of a constant, the keyword CONSTANT should precede the type of the specifier, as the example below shows: credit_limit CONSTANT REAL := 5000.00; This declaration names a constant of the type REAL and assigns an initial value of 5000 to the constant. The constant must be initialized in its declaration. Or else, you get a compilation error whenever the declaration is elaborated. (The procedure of a declaration by the PL/SQL compiler is known as the elaboration.)
Using COUNT The COUNT returns the number of elements that a collection presently contains. For instance, when a varray projects contains 15 elements, then the following IF con
Cause of Indeterminacy in SQL One root cause of indeterminacy in SQL lies in its implementation of comparison for equality. For certain system-defined types it is possible for
Use of Table Expressions - Expressing Constraint Conditions With the exception of key constraints, the examples in the theory book all explicitly reference at least one relvar
Definition of CROSS JOIN - SQL Let s = t1 CROSS JOIN t2, where t1 and t2 are table expressions optionally accompanied by range variables. Then: Note: Here T denotes Table
EXECUTE Privilege To call an invoker-rights routine straightforwardly, the users should have the EXECUTE privilege on that routine. By yielding the privilege, you permit a user
Records Records are the items of the type RECORD. The Records have exclusively named fields that can store the data values of various types. And hence, a record treat associate
What Is a Collection The collection is an ordered group of elements, all of similar type (for e.g. the grades for a class of students). Each element has a unique subscript whic
Declaring Cursor Variables Once a REF CURSOR type is define by you, and then you can declare the cursor variables of that type in any PL/SQL block or subprogram. In the exampl
INSERT Command in SQL Loosely speaking, INSERT takes the rows of a given source table and adds them to the specified target table, retaining all the existing rows in the targ
In Packages The Forward declarations also group logically related subprograms in the package. The subprogram specifications go in the package specification, & the subprogram b
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