Type versus representation confusion in sql, PL-SQL Programming

Assignment Help:

Type versus Representation Confusion in SQL

This describes how a value might have two or more distinct representations. For example, user-defined type POINT might have a declared possrep based on Cartesian coordinates and another based on polar coordinates. SQL has a system-defined type, TIMESTAMP, for values representing points in time, a timestamp being represented by a date, a time of day, and-optionally-a time zone, expressed as a displacement from UTC. Clearly any timestamp can be expressed in several different ways, using different time zones.

Three o'clock in the afternoon of December 31st, 2011 in UK, for example, is the same time as two o'clock in the morning of January 1st, 2012 in New Zealand. SQL treats those two representations as distinct values that compare equal, in like fashion to its treatment of character strings with trailing blanks, with similar consequences. If instead it had treated them as distinct representations of the same value, then the issue of indeterminacy would not have arisen.


Related Discussions:- Type versus representation confusion in sql

Using commit, Using COMMIT The COMMIT statements end the present trans...

Using COMMIT The COMMIT statements end the present transaction and make permanent any changes made during that transaction. Till you commit the changes, other users cannot acc

Triggers, At times, customers make mistakes in submitting their orders and ...

At times, customers make mistakes in submitting their orders and call to cancel the order. Brewbean’s wants to create a trigger that automatically updates the stock level of all pr

First step at defining type sid in sql, First Step at defining type SID in ...

First Step at defining type SID in SQL CREATE TYPE SID AS ( C VARCHAR(5) ) ; Explanation: TYPE SID announces that a type named SID is being defined to the syst

Package utl file in pl/sql, UTL_FILE: The Package UTL_FILE permits you...

UTL_FILE: The Package UTL_FILE permits your PL/SQL programs to read & write operating system (OS) text files. It gives a restricted version of the standard OS stream file I/O,

Keyword and parameter description - cursors, Keyword and Parameter Descript...

Keyword and Parameter Description select_statement: This is a query which returns a result set of the rows. Its syntax is such that of select_ into_statement without the IN

Rownum - sql pseudocolumns, ROWNUM The ROWNUM returns a number represe...

ROWNUM The ROWNUM returns a number representing the order in which a row was selected from the table. The first row selected has a ROWNUM of 1; the second row has a ROWNUM of

Exception_init pragma - pl/sql, EXCEPTION_INIT Pragma The pragma EXCEPT...

EXCEPTION_INIT Pragma The pragma EXCEPTION_INIT relates an exception name with an Oracle error number. Which allow you to refer to any internal exception by the name and to wri

Special cases of projection, Special cases of projection This section ...

Special cases of projection This section describes the identity projection, r {ALL BUT}, and the projection on no attributes, r { }, which yields TABLE_DUM when r is empty, ot

Using limit - collection method, Using LIMIT For nested tables, that h...

Using LIMIT For nested tables, that have no maximum size, the LIMIT returns NULL. For varrays, the LIMIT returns the maximum number of elements that a varray can have (that yo

Authorisations - privileges, Authorisations - Privileges As relational...

Authorisations - Privileges As relational theory is silent on the issue of authorisation, it offers nothing with which SQL's vast edifice in support of what it calls privilege

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