Definition of cross join - sql, PL-SQL Programming

Assignment Help:

Definition of CROSS JOIN - SQL

Let s = t1 CROSS JOIN t2, where t1 and t2 are table expressions optionally accompanied by range variables. Then:

Note: Here T denotes Table and R denotes Row

The heading Hs of s is the concatenation of the headings of t1 and t2, in that order.
If r1 is a row appearing n1 times in t1 and r2 is a row appearing n2 times in t2, then the row formed by concatenation of r1 and r2 in that order appears n1*n2 times in the body of s.

It follows that the degree of the result is the sum of the degrees of the operands and its cardinality is the product of their cardinalities, as with r1 TIMES r2.

Related Discussions:- Definition of cross join - sql

Keyword & parameter description - exception_init pragma, Keyword & Paramete...

Keyword & Parameter Description: PRAGMA: These keywords signify that the statement is a pragma (i.e. compiler directive). The Pragmas are processed at the compile time, n

Raise_application_error, Raise_application_error - procedure of package D...

Raise_application_error - procedure of package DBMS_STANDARD , allows to issue an user_defined error messages by stored sub-program or database trigger.

Using exception_init - user-defined exceptions, Using EXCEPTION_INIT T...

Using EXCEPTION_INIT To handle unnamed internal exceptions, you should use the OTHERS handler or the pragma EXCEPTION_INIT. The pragma is a compiler directive that can be th

Example of null operator - nino rule, Example of Null operator - NiNo Rule ...

Example of Null operator - NiNo Rule If we wanted to make HIGHER_OF adhere to "NULL in, NULL out"-let's call it the NiNo rule-we would have to write something like what is sho

Referencing records, Referencing Records Unlike the elements in a coll...

Referencing Records Unlike the elements in a collection, that are accessed using subscripts, the fields in a record are accessed by name. To reference an individual field, you

Scoping-naming conventions, Scoping Within the similar scope, all the de...

Scoping Within the similar scope, all the declared identifiers should be unique. So, even if their datatypes differ, the variables and parameters cannot share the similar name.

Creating a sql file, Creating a SQL file 1. Open a new file in Notepad...

Creating a SQL file 1. Open a new file in Notepad++ and save it to the location c:\mysql\bin, with the name lab8script.sql (the file extension should be .sql ). Add a MySQL co

Collection methods in pl sql, Collection Methods: The collection me...

Collection Methods: The collection method is a built-in function or procedure which operates on the collections and is called using the dot notation. The methods like the C

I need simple hosted sql database, Project Description: I want a small r...

Project Description: I want a small relational database to be built. I want the database to have the subsequent information tables: Employee Information Document storage

produce vertical output format- oracle, Create a Oracle procedure to produ...

Create a Oracle procedure to produce vertical output format when selecting rows from a database table.

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages