Cursor variables in pl sql, PL-SQL Programming

Assignment Help:

Cursor Variables:

 To execute the multi-row query, the Oracle opens an unnamed work region that stores the processing information. You can use an explicit cursor that names the work region, to access the information. Or, you can use the cursor variable that points to the work region. While a cursor always refers to similar query work region, a cursor variable can refer to various work regions. To create the cursor variables, you can define a REF CURSOR type, and then declare the cursor variables of that type.

The Cursor variables are such as C or Pascal pointers that hold the memory location (address) of a little item rather of the item itself. Therefore, declaring a cursor variable build a pointer, not an item.

1597_constant variable.png

Keyword and Parameter Description:

type_name:

This is a user-defined type specifier that is used in the subsequent declarations of the PL/SQL cursor variables.

REF CURSOR:

In PL/SQL, the pointers have datatype REF X, where REF is short form of REFERENCE and

X stands for the class of objects. And hence, the cursor variables have datatype REF CURSOR.

RETURN:

This keyword introduces the RETURN clause that specifies the datatype of the cursor variable result value. You can use the %ROWTYPE attribute in the RETURN clause to give a record type which presents a row in a database table or a row returned by a cursor or strongly typed cursor variable. You can also use the %TYPE attribute to give the datatype of a earlier declared record.

cursor_name:

These identify an explicit cursor earlier declared within the present scope.

cursor_variable_name:

These identify a PL/SQL cursor variable formerly declared within the present scope.

record_name:

These identify a user-defined record formerly declared within the present scope.

record_type_name:

These identify a RECORD type formerly defined within the present scope.

db_table_name:

These identify a database table (or view) that shuld be accessible when the declaration is elaborated.

%ROWTYPE:

These attributes provides a record type that presents a row in the database table or a row fetched from the cursor or strongly typed cursor variable. The Fields in the record and equivalent columns in the row have similar names and datatypes.

%TYPE:

These attributes provides the datatype of a formerly declared user-defined record.

 


Related Discussions:- Cursor variables in pl sql

Exit-when - iterative control, EXIT-WHEN The EXIT-WHEN statement permits...

EXIT-WHEN The EXIT-WHEN statement permits a loop to complete conditionally. Whenever the EXIT statement is encountered, the condition in the WHEN clause is computed. When the co

Create GUIs in PL/SQL, i NEED TO CREATE 3 guiS IN pl/sql sERVER PAGE FORM

i NEED TO CREATE 3 guiS IN pl/sql sERVER PAGE FORM

Updating tables in sql, Updating Tables in SQL The topic of updating b...

Updating Tables in SQL The topic of updating by describing the assignment operator, ":=" in Tutorial D. SQL uses a different syntax for assignment, using the key word SET and

Translate the given er schema into sql, Consider the schema for FreeCheckin...

Consider the schema for FreeChecking Bank, that we designed given below. Translate the given ER schema into SQL CREATE TABLE statements (indicating primary key, unique and foreign

Difference between 9i & 10g, Difference between 9i & 10G When Oracle r...

Difference between 9i & 10G When Oracle releases any new databases then it are having some discrepancy with them. But 10G is having much difference than oracle 9i has. Oracle

Relational algebra, Define basic operators of relational algebra with an ex...

Define basic operators of relational algebra with an example each

Control structure, Control Structures The Control structures are the mo...

Control Structures The Control structures are the most important PL/SQL extension to the SQL. Not only does PL/SQL let you manipulate Oracle data, it lets you process the data

Referencing records, Referencing Records Unlike the elements in a coll...

Referencing Records Unlike the elements in a collection, that are accessed using subscripts, the fields in a record are accessed by name. To reference an individual field, you

Pass the nulls to a dynamic sql, Pass the nulls to a dynamic SQL: Pas...

Pass the nulls to a dynamic SQL: Passing Nulls: Assume that you want to pass the nulls to a dynamic SQL statement. For illustration, you may write the EXECUTE IMMEDIATE

Sql, If two relations R and S are joined, then the non matching tuples of b...

If two relations R and S are joined, then the non matching tuples of both R and S are ignored in __________________.

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