Operators on tables and rows, PL-SQL Programming

Assignment Help:

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. For example, when appearing in a suitable context, the expression

(SELECT * FROM COURSE WHERE CourseId = CID ('C1'))

Yields the row denoted by

CAST (ROW ('C1', 'Database') AS

ROW (CourseId CID, Title VARCHAR (100)))

A row subquery whose table operand is empty yields a row in which every field is NULL.

Field Extraction: For extracting a field from a row, using dot qualification.


Related Discussions:- Operators on tables and rows

Using inner join, Using INNER JOIN INNER JOIN is used to retrieve the ...

Using INNER JOIN INNER JOIN is used to retrieve the data from all tables listed based on a condition of equality listed after keyword ON. If the condition is not meet, rows ar

Example of not exists operator - sql, Example of NOT EXISTS Operator - SQL ...

Example of NOT EXISTS Operator - SQL Example is a translation into SQL of the corresponding example, which is included there merely to show that for any scalar comparison the

Triffic light control system, write the program for traffic control system ...

write the program for traffic control system with 10 second, 15 secod, and 20 second delay

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

Enforce security in the database system, Question: (a) In the context o...

Question: (a) In the context of database security explain how the following database features help to enforce security in the database system: (i) Authorisation (ii) Access

Existential quantification - sql, Existential Quantification - SQL Ex...

Existential Quantification - SQL Existential quantification-stating that something is true of at least one object under consideration-can be expressed by OR(r,c), meaning tha

I want database development with analysis tools, Project Description: I ...

Project Description: I want a database for large governmental and private data sets on one country that will be easily extended to other countries in the future. Also, the datab

Autonomous versus nested transactions, Autonomous versus Nested Transaction...

Autonomous versus Nested Transactions Though an autonomous transaction is started by the other transaction, it is not a nested transaction for the reasons shown below: (i)

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

Between and not between operator in sql, BETWEEN and NOT BETWEEN Operator i...

BETWEEN and NOT BETWEEN Operator in SQL Example: Restricting exam marks to between 0 and 100 CREATE ASSERTION Marks_between_0_and_100 CHECK (NOT EXISTS (SELECT * FROM

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