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inserting objectsyou can use the insert statement to add objects to an object table in the illustration below you insert a person object into the
using operator derefyou cannot navigate through refs within the plsql procedural statements rather than you should use the operator deref in the sql
using operator refyou can retrieve refs by using the operator ref that like value takes as its argument a correlation variable in the illustration
using operator valueas you may expect the operator value returns the value of an object the value takes its argument a correlation variable for
selecting objectssuppose that you have run the sqlplus script below that creates object type person and object table persons and that you have
manipulating objectsyou can use an object type in the create table statement to indicate the datatype of a column when the table is created once you
calling constructorsthe calls to a constructor are allowed wherever the function calls are allowed similarly to the functions a constructor is called
accessing attributesyou can refer to an attribute only by its name not by its position in the object type to access or modify the value of an
initializing objectstill you initialize an object by calling the constructor for its object type the object is automatically null that is the object
declaring objectsyou can use the object types wherever built-in types like char or number can be used in the block below you can declare object r of
declaring and initializing objectsan object type is once defined and installed in the schema you can use it to declare the objects in any plsql
map and order methodsthe values of the scalar datatype like char or real have a predefined order that allows them to be compared while the instances
overloadingsimilar to packaged subprograms methods of the same type can be overloaded that is you can use similar name for various methods if their
parameter self in plsqlthe member methods recognize a built-in parameter named self that is an instance of the object type whether declared
methodsin normal a method is a subprogram declared in an object type specification using the keyword member or static the method cannot have similar
attributesjust similar to variable an attribute is declared with a name and datatype the name should be exclusive within the object type the datatype
components of an object typean object type encapsulates the operations and data therefore you can declare the methods and attributes in an object
role of abstraction in plsqlthe abstraction is a high-level description or model of a real-world entity the abstractions keep our daily lives
utlfilethe package utlfile permits your plsql programs to read amp write operating system os text files it gives a restricted version of the standard
dbmspipethe package dbmspipe allows various sessions to communicate over the named pipes a pipe is a region of memory used by one of the process to
dbmsoutputthe package dbmsoutput enables you to display output from the plsql subprograms and blocks that makes it easier to test and debug them the
product-specific packagesthe oracle and different oracle tools are supplied with the product-specific packages which help you to build the
package standardpackage named standard defines the plsql atmosphere the package specification globally declares the exceptions types and subprograms
package bodythe package specification is implemented by the package body that is the package body has the definition of every cursor and the
advantages of packagesthe benefits of the packages are as shown belowmodularitythe packages encapsulate logically associated items types and