Cursor for loops, PL-SQL Programming

Assignment Help:

Cursor FOR Loops

In most cases that need an explicit cursor, you can simplify the coding by using a cursor FOR loop rather of the OPEN, FETCH, and CLOSE statements. A cursor FOR loop implicitly declares its loop index as a record that shows a row fetched from the database. Then, it opens a cursor, repeatedly fetches rows of values from the result set into fields in the record, and after that closes the cursor when all rows have been processed. In the example below, the cursor FOR loop implicitly declares emp_rec as a record:

DECLARE

CURSOR c1 IS

SELECT ename, sal, hiredate, deptno FROM emp;

... BEGIN

FOR emp_rec IN c1 LOOP

...

salary_total := salary_total + emp_rec.sal; END LOOP;

To reference the individual fields in the record, you use dot notation, in which a dot (.) serves as the component selector.


Related Discussions:- Cursor for loops

Case sensitivity-naming conventions, Case Sensitivity Similar to all the...

Case Sensitivity Similar to all the identifiers, the variables, the names of constants, and parameters are not case sensitive. For illustration, PL/SQL considers the following n

Oracle, Literature review

Literature review

Closing a cursor variable, Closing a Cursor Variable The CLOSE stateme...

Closing a Cursor Variable The CLOSE statement disables the cursor variable. After that, the related result set is undefined. The syntax for the same is as shown below: CLOS

Using not null-declarations in sql, Using NOT NULL Besides assigning an ...

Using NOT NULL Besides assigning an initial value, the declarations can impose the NOT NULL constraint, as the example below shows: acct_id INTEGER(4) NOT NULL := 9999; You ca

Scope and visibility- pl/sql, Scope and Visibility The References to an ...

Scope and Visibility The References to an identifier are resolved according to its visibility and scope. The scope of an identifier is that area of a program unit (subprogram, b

Comparison operators - sql operators, Comparison Operators Usually, yo...

Comparison Operators Usually, you use the comparison operators in the WHERE clause of a data manipulation statement to form the predicates, that compare one expression to anot

Mutual recursion, Mutual Recursion The Subprograms are mutually recursi...

Mutual Recursion The Subprograms are mutually recursive if they directly or indirectly call each other. In the illustration below, the Boolean functions odd & even, that dete

Parameter and keyword description - update statement, Parameter and Keyword...

Parameter and Keyword Description:   table_reference: This keyword identifies the table or view that should be accessible when you execute the UPDATE statement, and for wh

Read-only operator (+) - sql, Read-Only Operator (+) - SQL The term r...

Read-Only Operator (+) - SQL The term read-only operator to the mathematical term function. Here I just need to add that the SQL standard reserves the term function for read-

Implicit cursors, Implicit Cursors The Oracle implicitly opens a curso...

Implicit Cursors The Oracle implicitly opens a cursor to process each SQL statement not related with an explicitly declared cursor. The PL/SQL lets you refer to the most recen

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