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

Pl/sql conditional control: if statements, Pl/sql Conditional Control: IF s...

Pl/sql Conditional Control: IF statements Frequently, it is necessary to take the alternative actions depending on the circumstances. The IF statement execute a series of statem

"not enforced" table constraints - sql, "Not Enforced" Table Constraints ...

"Not Enforced" Table Constraints A constraint that is not enforced is not really a constraint within the meaning of the act, but SQL does have such a concept and it needs to b

Special cases of projection, Special cases of projection This section ...

Special cases of projection This section describes the identity projection, r {ALL BUT}, and the projection on no attributes, r { }, which yields TABLE_DUM when r is empty, ot

Package standard in pl/sql, Package STANDARD package named STANDARD d...

Package STANDARD package named STANDARD defines the PL/SQL atmosphere. The package specification globally declares the exceptions, types, and subprograms that are available a

Keyword and parameter description - cursors, Keyword and Parameter Descript...

Keyword and Parameter Description select_statement: This is a query which returns a result set of the rows. Its syntax is such that of select_ into_statement without the IN

Write sql queries, Write SQL queries to solve the following specifications....

Write SQL queries to solve the following specifications. Include the query AND THE OUTPUT.  A screen dump of the output is acceptable. Show as many rows as you can. A screen dump i

Use external routines - improve performance of application, Use External Ro...

Use External Routines The PL/SQL is particular for the SQL transaction processing. Therefore, several tasks are more quickly completed in a lower-level language like C that is

Using limit - collection method, Using LIMIT For nested tables, that h...

Using LIMIT For nested tables, that have no maximum size, the LIMIT returns NULL. For varrays, the LIMIT returns the maximum number of elements that a varray can have (that yo

Advantages of packages, Advantages of Packages The benefits of the Pack...

Advantages of Packages The benefits of the Packages are as shown below: Modularity The Packages encapsulate logically associated items, types, and subprograms in the

Update command- sql, UPDATE Command- SQL Loosely speaking, UPDATE chan...

UPDATE Command- SQL Loosely speaking, UPDATE changes some of the column values of some existing rows of its target table. Thus, although some rows disappear from the target an

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