Effect of anonymous columns, PL-SQL Programming

Assignment Help:

Effect of Anonymous Columns

Now, recall that a VALUES expression denotes a table with undefined column names. If an initial value is to be specified when a base table is created, column definitions have to be implied by that initial value, so the question arises, how can a VALUES expression provide the initial value for a base table? The answer is that you have to learn an extra syntactic construct for that purpose, shown in Example.

Example: Specifying an initial value for a base table.

CREATE TABLE ENROLMENT (StudentId, Name, CourseId)

AS (VALUES (SID ('S1'), 'Anne', CID ('C1')),

(SID ('S2'), 'Boris', CID ('C1')))

WITH DATA;

Explanation:

  1. (StudentId, Name, CourseId) provides the names, positionally corresponding to the anonymous columns of the AS table.
  2. WITH DATA specifies that the given table is indeed to be the initial value. Curiously, this is required, unless WITHOUT DATA is written instead, in which case the AS table serves only to determine the declared types of the columns of the base table.
  3. SQL does not allow constraints to be declared if AS is used in place of explicit column definitions.

Related Discussions:- Effect of anonymous columns

Using host arrays - bulk bind performance improvement, Using Host Arrays ...

Using Host Arrays The Client-side programs can use anonymous PL/SQL blocks to bulk-bind input and output host arrays. However, this is the well-organized way to pass the colle

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

Example of using aggregation on nested tables, Example of Using Aggregation...

Example of Using Aggregation on Nested Tables Example: How many students sat each exam WITH C_ER AS (SELECT CourseId, CAST (TABLE (SELECT DISTINCT StudentId, Mark FROM EXAM

Sql queries, SELECT a.child_fname,a.child_lname,concat(b.parent_title,b.par...

SELECT a.child_fname,a.child_lname,concat(b.parent_title,b.parent_fname), b.parent_lname,b.parent_tphone FROM child a,parent b WHERE a.parent_id=b.parent_id ORDER BY a.child_fnam

Dbms, DBMS: The answer to this question is of course given in of the t...

DBMS: The answer to this question is of course given in of the theory book. This book is concerned with SQL DBMSs and SQL databases in particular. Soon we will be looking a

Oracle 10g new features and differences , Oracle 10G new features:- Au...

Oracle 10G new features:- Automatic Database Diagnostic Monitor System Advancements - these methods will provides several methods for extracting reports through the Automatic

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

Check constraints in sql, CHECK Constraints in SQL A CHECK constraint ...

CHECK Constraints in SQL A CHECK constraint is a table constraint defined using the key word CHECK, as already illustrated in several examples in this chapter. In particular,

Data abstraction, Data Abstraction The Data abstraction extracts the im...

Data Abstraction The Data abstraction extracts the important properties of data while ignoring the not necessary details. Once you design a data structure, you can fail to reme

Using raise_application_error - user-defined exceptions, Using raise_applic...

Using raise_application_error The Package DBMS_STANDARD that is supplied with Oracle gives language facilities that help your application to interact with Oracle. For illustra

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