Cursor variables, PL-SQL Programming

Assignment Help:

What Are Cursor Variables ?

The Cursor variables are like C or Pascal pointers that hold the memory location (address) of some item rather of the item itself. Therefore, declaring a cursor variable creates a pointer, not an item. In the PL/SQL, the pointer has a datatype REF X, where REF is short form for the REFERENCE and X stands for the class of objects. Therefore, a cursor variable has the datatype REF CURSOR.

To execute a multi-row query, the Oracle opens an unnamed work region which stores processing the information. To access the information, you can use an explicit cursor that names the work area. Or, you can use a cursor variable that points to the work region. While the cursor always refers to the similar query work region, a cursor variable can refer to various work regions. Therefore, the cursors and cursor variables are not interoperable.


Related Discussions:- Cursor variables

Theory of biogenesis, THEORY OF BIOGENESIS - This theory explains th...

THEORY OF BIOGENESIS - This theory explains that the existing living organisms originated from pre-existing living beings not from non living entities. This concept of or

Committing and rolling back - autonomous transaction, Committing and Rollin...

Committing and Rolling Back The COMMIT and ROLLBACK end the active autonomous transaction but do not exit the autonomous routine. As the figure shows, if one transaction ends,

Order of evaluation-pl/sql expressions , Order of Evaluation When you do...

Order of Evaluation When you do not use the parentheses to specify the order of evaluation, the operator precedence determine the order. Now compare the expressions below: NOT

Sequential control - pl/sql, Sequential Control Dissimilar to the IF and ...

Sequential Control Dissimilar to the IF and LOOP statements, the GOTO and NULL statements are not important to the PL/SQL programming. The configuration of PL/SQL is such that th

Fetching from a cursor variable, Fetching from a Cursor Variable The F...

Fetching from a Cursor Variable The FETCH statement retrieve rows one at a time from the product set of a multi-row query. The syntax for the same is as shown: FETCH {curso

Write sql code that will create the writes table, Question: Consider th...

Question: Consider the following relations (primary keys are underlined): AUTHOR (ANo, aname, address, speciality) PUBLISHER (PNo, pname, Location) BOOK (BNo, Title, ISBN,

Literals in pl/sql, Literals A literal is an explicit numeric, string...

Literals A literal is an explicit numeric, string, character, or Boolean value not represented by an identifier. Numeric literal 147 and the Boolean literal FALSE are some of

Semidifference and not - sql, Semidifference and NOT - SQL In this sec...

Semidifference and NOT - SQL In this section first describe the relational difference operator, named MINUS. Example here shows SQL's closest counterpart of that operator.

%found - implicit cursor attributes, %FOUND Until the SQL data manipul...

%FOUND Until the SQL data manipulation statement is executed, the %FOUND yields NULL. Afterward, the %FOUND yields TRUE, when an INSERT, UPDATE, or DELETE statement affected o

Using aliases-declarations in sql, Using Aliases The Select-list items f...

Using Aliases The Select-list items fetched from a cursor related with the %ROWTYPE should have simple names or, if they are expressions, should have aliases. In the example bel

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