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

Manipulating individual elements - pl/sql, Manipulating Individual Elements...

Manipulating Individual Elements Faraway you have manipulated an entire collection. Within the SQL, to manipulate the individual elements of the collection, and then use the ope

Keyword and parameter description - delete statement, Keyword and Parameter...

Keyword and Parameter Description: table_reference: This specifies a table or view that should be accessible when you execute the DELETE statement, and for that you must

Theory of panspermia - origin of life, THEO R Y OF PANSPERMIA - Arrh...

THEO R Y OF PANSPERMIA - Arrhenius (1908) postulated the cosmic panspermia theory that claims that organisms existed throughout the universe, and their spores, etc., could

Loop labels- iterative control, Loop Labels Like the PL/SQL blocks, loop...

Loop Labels Like the PL/SQL blocks, loops can also be labeled. The label, an undeclared identifier enclosed by double angle brackets, should appear at the beginning of the LOOP

Need for dynamic sql - pl sql , Need for Dynamic SQL: You need dynamic...

Need for Dynamic SQL: You need dynamic SQL in the situations as follows: 1) You would like to execute a SQL data definition statement (like CREATE), a data control statemen

Use bulk binds - improve performance of application, Use Bulk Binds If...

Use Bulk Binds If SQL statements execute inside a loop using the collection elements as bind variables, context switching between the PL/SQL & SQL engines can slow down the ex

Advantages of subprograms, Advantages of Subprograms The Subprograms g...

Advantages of Subprograms The Subprograms give extensibility; that is, tailor the PL/SQL language to suit your requirements. For illustration, if you require a procedure which

Ending transactions, Ending Transactions A good quality programming pr...

Ending Transactions A good quality programming practice is to commit or roll back every transaction explicitly. Whether you rollback or issue the commit in your PL/SQL program

Parameter and keyword description - update statement, Parameter and Keyword...

Parameter and Keyword Description: table_reference: This keyword identifies the table or view that should be accessible when you execute the UPDATE statement, and for wh

Number types in pl/sql, Number Types The Number types permit you to sto...

Number Types The Number types permit you to store the numeric data (real numbers, integers, and floating-point numbers), show quantities, and do computations. BINARY_INTEG

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages