Obtaining a natural join by specifying the common columns, PL-SQL Programming

Assignment Help:

Obtaining a natural join by specifying the common columns

Synatax:

SELECT * FROM IS_CALLED JOIN IS_ENROLLED_ON USING ( StudentId )

However, a named columns join doesn't always have an equivalent formulation using NATURAL JOIN. That's because although each USING column must be a common column, it is not necessary to specify all the common columns.

A common column whose name does not appear in the USING list gives rise to two columns of that name in the result, which therefore does not represent a relation. To cater for cases where the columns used for matching purposes are not common columns, and/or the matching operator is not "=", the required joining condition can be spelled out as shown in Example, in parentheses following the key word ON.


Related Discussions:- Obtaining a natural join by specifying the common columns

Calculate days between ordering and shipping, An analyst in the quality ass...

An analyst in the quality assurance office reviews the time lapse between receiving an order and shipping an order. Any orders that have not been shipped within a day of the order

Execute immediate statement - syntax, EXECUTE IMMEDIATE Statement   Th...

EXECUTE IMMEDIATE Statement   The EXECUTE IMMEDIATE statement prepare (parses) and instantly executes a dynamic SQL statement or an anonymous PL/SQL block. Syntax:

CURSOR, #quesWrite a cursor to open an employee database and fetch the empl...

#quesWrite a cursor to open an employee database and fetch the employee record whose age is greater than 45.tion..

Pits, PITS Depressions in secondary cell wall is called pit. A pi...

PITS Depressions in secondary cell wall is called pit. A pit present on the free cell wall surface without its partner is called Blind pit. It consists of 2 parts -

Assignment source not a literal - variable, Assignment Source Not a Literal...

Assignment Source Not a Literal - Variable Syntax: SET SN = SID (SUBSTRING (SN.C FROM 1 FOR 1)||'5');

Using operator value in pl sql, Using Operator VALUE: As you may expec...

Using Operator VALUE: As you may expect, the operator VALUE returns the value of an object. The VALUE takes its argument a correlation variable.  For illustration, to return a

Sql query for testing triggers and stored procedures , Description: Dem...

Description: Demonstrate your knowledge of PL/SQL programming by writing and thoroughly testing triggers and stored procedures associated with an e-commerce application that pr

Updating a variable, Updating a Variable Assignment of an attribute va...

Updating a Variable Assignment of an attribute value in a variable of a structured type Synatx: SET SN.C = 'S2'; As in Example the entire statement is equivalent to a

Pascal programming and mysql programming, I have a Pascal Source file that ...

I have a Pascal Source file that needs to be compiled into a Service. In addition, there are various functions (Pascal Procedures I guess) that need to be created to Read and Write

Using rollback - , Using ROLLBACK The ROLLBACK statements end the pres...

Using ROLLBACK The ROLLBACK statements end the present transaction and undo any change made during the transaction. The Rolling back is helpful for two reasons. Firstly, if yo

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