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

Fetch statement - syntax, FETCH Statement The FETCH statement retrieve ...

FETCH Statement The FETCH statement retrieve rows of data one at a time from the result set of the multi-row query. The data is stored in fields or variables which correspond t

Using set transaction, Using SET TRANSACTION You use the SET TRANSACTI...

Using SET TRANSACTION You use the SET TRANSACTION statement to begin the read-only or read-write transaction, start an isolation level, or assign your present transaction to a

Package - pl/sql programming, What Is a Package? The package is a sch...

What Is a Package? The package is a schema object that group logically related PL/SQL items, types, and subprograms. The Packages usually have 2 parts, a specification & a bo

Operators on tables and rows, Operators on Tables and Rows Row Extrac...

Operators on Tables and Rows Row Extraction TUPLE FROM r, SQL has row subqueries. These are just like scalar subqueries except that they may specify more than one column.

Merge two data sources to sql azure database, Project Description: I hav...

Project Description: I have two types of data sources. One that is a list in SharePoint and another that is an access desktop database. The access desktop database is fairly com

Sql outer join, SQL outer join SELECT * FROM IS_CALLED NATURAL LEFT...

SQL outer join SELECT * FROM IS_CALLED NATURAL LEFT JOIN IS_ENROLLED_ON Note that adding LEFT to an invocation of CROSS JOIN has no effect unless the right-hand operand

Declaring records, Declaring Records Whenever you define a RECORD type...

Declaring Records Whenever you define a RECORD type, you may declare records of that type, as the illustration shows: DECLARE TYPE StockItem IS RECORD ( item_no INTEG

Pass the nulls to a dynamic sql, Pass the nulls to a dynamic SQL: Pas...

Pass the nulls to a dynamic SQL: Passing Nulls: Assume that you want to pass the nulls to a dynamic SQL statement. For illustration, you may write the EXECUTE IMMEDIATE

Cursor for loops, Cursor FOR Loops In most cases that need an explicit ...

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

Recursion versus iteration, Recursion versus Iteration Dissimilar the i...

Recursion versus Iteration Dissimilar the iteration, recursion is not crucial to PL/SQL programming. Any problem which can be solved using recursion can be solving using the it

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