Example of table literal - sql, PL-SQL Programming

Assignment Help:

Example of Table Literal - SQL

Example: A Table Literal (correct version)

VALUES

('S1', 'C1', 'Anne'),

('S1', 'C2', 'Anne'),

('S2', 'C1', 'Boris'),

('S3', 'C3', 'Cindy'),

('S4', 'C1', 'Devinder')

Now, the question arises, what is the (table) type of the table shown in Example? For that matter, what is the (row) type of ('S1', 'C1', and 'Anne')? In particular, what are the field names of those three fields, which would become column names for the containing table? The short answer is that they are determined by the context in which the expression appears. Because the components are distinguished anyway by ordinal position, the field names sometimes serve little or no purpose. In fact several fields are permitted to acquire the same name. Also, sometimes the context does not provide any names at all, in which case, according to the standard, each field is assigned a unique but unpredictable name.

Examples arising as we go along will make this issue a little clearer. I shall use the term anonymous column to refer to a column whose name is unpredictable and therefore effectively undefined. Note carefully that if the word ROW is omitted and the row consists of a single field, then the parentheses can also be omitted. Thus, VALUES 'S1' denotes a table consisting of a single column and a single row, the SQL counterpart of RELATION { TUPLE { StudentId 'S1' } } (though the SQL counterpart has nothing corresponding to the attribute name).


Related Discussions:- Example of table literal - sql

Recursive subprograms, Recursive Subprograms The recursive subprogram ...

Recursive Subprograms The recursive subprogram is the one that calls itself. Think of a recursive call as a call to a few other subprograms that does the similar task as your

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

I want customer management program, This is a Customer Management project. ...

This is a Customer Management project. Customer data is presented in a text file. The program will load this text data into its DB columns. The data mapping is user definable. User

Using cursor attributes - bulk bind performance improvement, Using Cursor A...

Using Cursor Attributes To process the SQL data manipulation statements, the SQL engine must opens an implicit cursor named SQL. This cursor's attributes (%FOUND, %NOTFOUND, %

Write sql queries, Write SQL queries to solve the following specifications....

Write SQL queries to solve the following specifications. Include the query AND THE OUTPUT.  A screen dump of the output is acceptable. Show as many rows as you can. A screen dump i

Pl/sql conditional control: if statements, Pl/sql Conditional Control: IF s...

Pl/sql Conditional Control: IF statements Frequently, it is necessary to take the alternative actions depending on the circumstances. The IF statement execute a series of statem

Package body, The Package Body The package specification is implemented...

The Package Body The package specification is implemented by the package body. That is, the package body has the definition of every cursor and the subprogram declared in the p

Tautology - equivalences rules, Tautology - Equivalences Rules: If the...

Tautology - Equivalences Rules: If there Tautologies are not all the time as much easy to note as the one above so than we can use these truth tables to be definite that a sta

Operator precedence-pl/sql expressions , Operator Precedence The operati...

Operator Precedence The operations within an expression are completed in a particular order depending on their precedence (priority). The table shows the default order of the op

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