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

Using savepoint, Using SAVEPOINT The SAVEPOINT names and marks the pre...

Using SAVEPOINT The SAVEPOINT names and marks the present point in the processing of a transaction. Used with the ROLLBACK TO statement, the savepoints undo parts of a transac

Creating a table, Creating a Table Syantax: CREATE TABLE ENROL...

Creating a Table Syantax: CREATE TABLE ENROLMENT (StudentId SID, Name   VARCHAR (30) NOT NULL, CourseId CID, PRIMARY KEY (StudentId, CourseId)) ; Explan

Table comparison - sql, Table Comparison - SQL The following definitio...

Table Comparison - SQL The following definitions for relation comparisons: Let r1 and r2 be relations having the same heading. Then: r1 ⊆ r2 is true if every tuple of r1

Functions in pl/sql, Functions   The function is a subprogram that cal...

Functions   The function is a subprogram that calculates a value. The Functions and procedures are structured similar, except that the functions have a RETURN clause. You can

Delete statement - syntax, DELETE Statement The DELETE statement elimin...

DELETE Statement The DELETE statement eliminates whole rows of data from the specified table or view. Syntax:

Parameter default values, Parameter Default Values As the illustration ...

Parameter Default Values As the illustration below shows, you can initialize the IN parameters to the default values. In that way, you can pass various numbers of actual par

Cursors in pl/sql, Cursors The Oracle uses work areas to execute the SQ...

Cursors The Oracle uses work areas to execute the SQL statements and to store process information. A PL/SQL construct known as the cursor. Let's you assume name a work area and

Object types and collections - performance of application, Use Object Types...

Use Object Types and Collections The Collection types and object types increase your efficiency by allowing for the realistic data modeling. The Complex real-world entities an

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

Example of except operator - sql, Example of EXCEPT Operator - SQL Ex...

Example of EXCEPT Operator - SQL Example, like its counterpart in the theory book, illustrates the convenience of allowing any table expression to be the source for an INSERT

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