Usefulness of data type, PL-SQL Programming

Assignment Help:

Usefulness of Data Type

In SQL, as in most computer languages, a type can be used for constraining the values that are permitted to be used for some purpose. In particular, it can be used for constraining:

  1. The values that can be assigned to a variable
  2. The values that can be substituted for a parameter
  3. The values that an operator can yield when invoked
  4. The values that can appear in a given column of a table

In each of the above cases, the type used for the purpose in question is the declared type of the variable, parameter, operator, or column, respectively. As a consequence, every expression denoting a value has a declared type too, whether that expression be a literal, a reference to a variable, parameter, or column, or an invocation of an operator. Thus SQL is able to detect errors at "compile time"- by mere inspection of a given script - that would otherwise arise, and cause much more inconvenience, at run time (when the script is executed).


Related Discussions:- Usefulness of data type

Manipulating collections-nested table examples, Manipulating Collections ...

Manipulating Collections Within PL/SQL, the collections add procedural power and flexibility. The biggest benefit is that your program can compute subscripts to process the spec

Identifiers in pl/sql, Identifiers You use identifiers to name the PL/S...

Identifiers You use identifiers to name the PL/SQL program items and units that include constants, variables, cursors, exceptions, cursor variables, subprograms, and packages.

Disjunction - sql, Disjunction (OR, ∨) Again we have nine rows instead...

Disjunction (OR, ∨) Again we have nine rows instead of just four and again, when unknown is not involved, the rows are as for 2VL. Also, when anything is paired with true, t

Albeit simple method , Albeit simple method : These all the truth tabl...

Albeit simple method : These all the truth tables give us our first as albeit simple method for proving a theorem: where check whether it can be written in propositional logic

Using delete - collection method, Using DELETE This process has three ...

Using DELETE This process has three forms. The DELETE removes all elements from the collection. DELETE(n) removes the nth element from the nested table. When n is null, then D

Second step at defining type sid in sql, Second Step at defining type SID i...

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

Role of abstraction in pl/sql, Role of Abstraction in pl/sql: The abst...

Role of Abstraction in pl/sql: The abstraction is a high-level description or model of a real-world entity. The Abstractions keep our daily lives convenient. They help us ca

Using exists - collection methods, Using EXISTS The EXISTS(n) returns ...

Using EXISTS The EXISTS(n) returns TRUE if the nth element in a collection exist. Or else, EXISTS(n) returns FALSE. Primarily, you use EXISTS with DELETE to maintain the spars

For-loop -iterative control, FOR-LOOP While the number of iterations thr...

FOR-LOOP While the number of iterations through a WHILE loop is unknown till the loop completes, then the number of iterations through a FOR loop is known before the loop is ent

%notfound - explicit cursor attributes, %NOTFOUND The %NOTFOUND is log...

%NOTFOUND The %NOTFOUND is logical, opposite of the %FOUND. The %NOTFOUND yields FALSE if the last fetch returned a row, or TRUE when the final fetch failed to return a row. I

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