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

Example of using aggregation on nested tables, Example of Using Aggregation...

Example of Using Aggregation on Nested Tables Example: How many students sat each exam WITH C_ER AS (SELECT CourseId, CAST (TABLE (SELECT DISTINCT StudentId, Mark FROM EXAM

Authorize and fetch data from instagram, Authorize and fetch data from Inst...

Authorize and fetch data from Instagram Project Description: Incorporate Instagram feed on mobile site platform: c#, ms sql, jquerymobile, jquery Web admin Author

Sql, Write a cursor to open an employee database and fetch the employee rec...

Write a cursor to open an employee database and fetch the employee record whose age is greater than 45

Updating variables, Updating Variables For assignment, SQL uses the ke...

Updating Variables For assignment, SQL uses the key word SET, as in SET X = X + 1 (read as "set X equal to X+1") rather than X: = X + 1 as found in many computer languages.

Need database development with analysis tools, Need Database Development wi...

Need Database Development with Analysis Tools Project Description: I want a database for large governmental and private data sets on one country that can be simply extended t

Some varray examples-manipulating collections, Some Varray Examples In S...

Some Varray Examples In SQL Plus, assume that you define an object type Project, as described below: SQL> CREATE TYPE Project AS OBJECT ( 2 project_no NUMBER(2), 3 title VARCHA

Using rename in combination with join - sql, Using RENAME in combination wi...

Using RENAME in combination with JOIN - SQL Example gives pairs of ids of students having the same name, by joining two renamings of IS_CALLED. Example gives an equivalent ex

Manipulating local collections - pl/sql, Manipulating Local Collections ...

Manipulating Local Collections Within PL/SQL, to manipulate the local collection, by using the  TABLE and CAST operators . The operands of CAST are a collection declared locally

Effects of null operator, Effects of NULL Operator As a general rule-b...

Effects of NULL Operator As a general rule-but not a universal one-if NULL is an argument to an invocation of a system-defined read-only operator, then NULL is the result of t

Grouping and ungrouping in sql, Grouping and Ungrouping in SQL Example...

Grouping and Ungrouping in SQL Example specifying EXAM_MARK in place of COURSE in the main FROM clause. Example: Obtaining C_ER2 from EXAM_MARK SELECT CourseId, CAST

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