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

Difference between implicit and explicit cursor, Implicit Cursor is declare...

Implicit Cursor is declared and used by the oracle environment internally. while the explicit cursor is declared and used by the external user. more over implicitly cursors are no

Declaring and initializing objects in pl/sql, Declaring and Initializing Ob...

Declaring and Initializing Objects: An object type is once defined and installed in the schema; you can use it to declare the objects in any PL/SQL, subprogram, block or packa

Cursor attributes in pl sql, Cursor Attributes   The Cursors and curso...

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 bulk collect clause- bulk bind performance improvement, Using the BUL...

Using the BULK COLLECT Clause The keywords BULK COLLECT specify the SQL engine to bulk-bind output collections before returning them to the PL/SQL engine. You can use these ke

%type - cursors, %TYPE: This attribute gives the datatype of a formerly...

%TYPE: This attribute gives the datatype of a formerly declared collection, cursor variable, object, field, record, database column, or variable. Datatype: This is simply

Using prior and next - collection method, Using PRIOR and NEXT The PRI...

Using PRIOR and NEXT The PRIOR(n) returns the index number that precede index n in a collection. The NEXT(n) returns the index number which succeed the index n. If n has no pr

Triffic light control system, write the program for traffic control system ...

write the program for traffic control system with 10 second, 15 secod, and 20 second delay

Procedures - syntax, Procedures The procedure is a subprogram which can...

Procedures The procedure is a subprogram which can take parameters and be invoked. Normally, you can use a procedure to perform an action. The procedure has 2 sections: the spe

When or then key constraints, WHEN or THEN Key Constraints Suppose a t...

WHEN or THEN Key Constraints Suppose a table has two columns representing a period of time throughout which the information conveyed by the other columns is recorded as having

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