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

Declaring records, Declaring Records Whenever you define a RECORD type...

Declaring Records Whenever you define a RECORD type, you may declare records of that type, as the illustration shows: DECLARE TYPE StockItem IS RECORD ( item_no INTEG

Logical operators-pl/sql expressions , Logical Operators The logical op...

Logical Operators The logical operators AND, NOT, and OR follow the tri-state logic shown in table below. The AND and OR are binary operators; NOT is a unary operator.

Structure of an object type in pl/sql, Structure of an Object Type: Si...

Structure of an Object Type: Similar to package, an object type has 2 parts: the specification and the body. The specification is the interface to your applications; it declar

Albeit simple method , Albeit simple method : These all the truth tabl...

Albeit simple method : These all the truth tables give us our first as albeit simple method for proving a theorem: where check whether it can be written in propositional logic

Second step at defining type sid in sql, Second Step at defining type SID i...

Second Step at defining type SID in SQL CREATE TYPE SID AS VARCHAR(5) ; Explanation: TYPE SID announces that a type named SID is being defined to the system.

Group and having query, Using a join on 2 tables, select all columns and 10...

Using a join on 2 tables, select all columns and 10 rows from the 2 tables without the use of a Cartesian product. Query: SELECT * FROM EMPLOYEE1 E JOIN STAFF S ON E.EMP_

Tautology - equivalences rules, Tautology - Equivalences Rules: If the...

Tautology - Equivalences Rules: If there Tautologies are not all the time as much easy to note as the one above so than we can use these truth tables to be definite that a sta

Cursor attributes in dynamic sql - pl sql, Using Cursor Attributes: Ev...

Using Cursor Attributes: Every cursor has 4 attributes: %NOTFOUND, %FOUND, %ISOPEN, and %ROWCOUNT. If appended to the cursor name, they return the helpful information about

Cursor variables, Cursor Variables Similar to a cursor, cursor variable...

Cursor Variables Similar to a cursor, cursor variable points to the current row in the result set of a multi-row query. But, dissimilar a cursor, a cursor variable can be opene

Operators on tables and rows, Operators on Tables and Rows Row Extrac...

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.

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages