What is a collection, PL-SQL Programming

What Is a Collection


The collection is an ordered group of elements, all of similar type (for e.g. the grades for a class of students). Each element has a unique subscript which determines its position in the collection. The PL/SQL offers two collection types. The Items of type TABLE are either index-by tables or nested tables (that extend the functionality of the index-by tables). The Items of type VARRAY are varrays (short for the variable-size arrays).

The Collections works like the arrays found in most of the third-generation programming languages. Though, collections can have only one dimension and should be indexed by the integers. (In few languages like Ada and Pascal, the arrays can have multiple dimensions and can be indexed by the enumeration types.)

The Collections can store instances of an object type and, on the contrary, can be attributes of an object type. The collections can also be passed as parameters. Therefore, you can use them to move the columns of data into and out of the database tables or between client-side applications and stored subprograms. Moreover, you can define the collection types in a PL/SQL package, and then use them programmatically in your applications.

 

 

Posted Date: 10/3/2012 6:27:23 AM | Location : United States







Related Discussions:- What is a collection, Assignment Help, Ask Question on What is a collection, Get Answer, Expert's Help, What is a collection Discussions

Write discussion on What is a collection
Your posts are moderated
Related Questions
Keys in SQL SQL support for keys in the following respects: SQL does not require at least one key for every base table. If no key is explicitly declared, then KEY {ALL B

Synonyms You can create the synonyms to provide location transparency for the remote schema objects like tables, views, sequences, stand-alone subprograms, and packages. Though,

Closing a Cursor Variable The CLOSE statement disables the cursor variable. After that, the related result set is undefined. The syntax for the same is as shown below: CLOS

Cursor FOR Loops In most cases that need an explicit cursor, you can simplify the coding by using a cursor FOR loop rather of the OPEN, FETCH, and CLOSE statements. A cursor FO

%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

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

Built-In Functions The PL/SQL provides a lot of powerful functions to help you to manipulate the data. These built-in functions fall into the categories as shown below: error r

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

Project Description: I want to rebuild it and add better content to it It will include up to 5 forms The data will be saved on SQL server and the data access layer could b

Restriction in SQL Syntax: SELECT DISTINCT StudentId FROM IS_CALLED WHERE Name = 'Boris' The WHERE clause operates on the result of the FROM clause in analogo