Referencing records, PL-SQL Programming

Assignment Help:

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 can use the dot notation and the syntax which is as shown:

record_name.field_name

For illustration, you reference field hire_date in record emp_info as shown:

emp_info.hire_date ...

When calling a function which returns a user-defined record, use the syntax below to reference the fields in the record:

function_name(parameter_list).field_name

For illustration, the call to function nth_highest_sal references to the field salary in record emp_info:

DECLARE

TYPE EmpRec IS RECORD (

emp_id NUMBER(4),

job_title CHAR(14),

salary REAL(7,2));

middle_sal REAL;

FUNCTION nth_highest_sal (n INTEGER) RETURN EmpRec IS

emp_info EmpRec;

BEGIN

...

RETURN emp_info; -- return record

END;

BEGIN

middle_sal := nth_highest_sal(10).salary; -- call function

When calling a parameter less function, following syntax can be use:

function_name().field_name -- note empty parameter list

To reference the nested fields in a record returned by a function, use the extended dot notation. The syntax is as shown:

function_name(parameter_list).field_name.nested_field_name

For illustration, the following call to function item references to the nested field minutes in record item_info:

DECLARE

TYPE TimeRec IS RECORD (minutes SMALLINT, hours SMALLINT);

TYPE AgendaItem IS RECORD (

priority INTEGER,

subject VARCHAR2(100),

duration TimeRec);

FUNCTION item (n INTEGER) RETURN AgendaItem IS

item_info AgendaItem;

BEGIN

...

RETURN item_info; -- return record

END;

BEGIN

...

IF item(3).duration.minutes > 30 THEN ... -- call function

END;


Related Discussions:- Referencing records

Definition of from - sql, Definition of FROM - SQL Recall that the ope...

Definition of FROM - SQL Recall that the operand of FROM is denoted by a commalist, each element of that commalist being a table expression optionally accompanied by a range v

Map and order methods, Map and Order Methods: The values of the scalar...

Map and Order Methods: The values of the scalar datatype like CHAR or REAL have a predefined order that allows them to be compared. While, the instances of an object type has

Parameter and keyword description - select into statement, Parameter and Ke...

Parameter and Keyword Description: select_item: This select_item is a value returned by the SELECT statement, and then assigned to the equivalent variable or field in the

Sql queries-oracle , 1- You can check attribute names from each table in D...

1- You can check attribute names from each table in DBF11 by running for example:  desc dbf11.Member;  desc dbf11.Agent;  desc dbf11.Producer; Because some attribute names in

Organic evolution, Organi c Evolution Evolution is a slow continuou...

Organi c Evolution Evolution is a slow continuous, irreversible and natural process of change to give rise to advance and diverse forms of life i.e. formation of new specie

Inner join, Inner Join We have learned how to retrieve data from one t...

Inner Join We have learned how to retrieve data from one table by using SELECT statement. But, as we have learned, normalized relational databases mean the data is spread betw

Using count, Using COUNT The COUNT returns the number of elements that...

Using COUNT The COUNT returns the number of elements that a collection presently contains. For instance, when a varray projects contains 15 elements, then the following IF con

Naming conventions-pl/sql, Naming Conventions The similar naming conventi...

Naming Conventions The similar naming conventions apply to all PL/SQL program items and units including the variables, cursors, constants, cursor variables, procedures, exception

Assignment of DBMS in SQL server, i have an assignment of DBMS subject, thi...

i have an assignment of DBMS subject, this assignment is based on SQL server and power BI

Database values-assignments in pl/sql, Database Values You can use the S...

Database Values You can use the SELECT statement to have the Oracle assign values to a variable. For Each and every item in the select list, there must be a matching, type-compa

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