Relational operators and logical operators, PL-SQL Programming

Assignment Help:

Relational Operators and Logical Operators

It prepares the ground for subsequent sections in which each specific relational operator is paired with its logical counterpart, such that, for example, r1 JOIN r2 denotes the relation representing the extension of the predicate p1 AND p2, the conjunction of the predicates for the operand relations. It follows that where we can find SQL counterparts of those relational operators, invocations of those counterparts will in turn represent extensions of the predicates.

Related Discussions:- Relational operators and logical operators

Keyword, what is the use of declare keyword

what is the use of declare keyword

Using operator ref - manipulating objects pl sql, Using Operator REF: ...

Using Operator REF: You can retrieve refs by using the operator REF that, like VALUE, takes as its argument a correlation variable. In the illustration below, you retrieve one

When are constraints checked - sql, When Are Constraints Checked Unde...

When Are Constraints Checked Under the model constraints are conceptually checked at all statement boundaries (and only at statement boundaries). By default the same is true

Currval and nextval - sql pseudocolumns, CURRVAL and NEXTVAL The serie...

CURRVAL and NEXTVAL The series is a schema object which generates the sequential numbers. Whenever you form a sequence, you can specify its primary value and an increment. T

Declaring subprograms, Declaring Subprograms You can declare subprog...

Declaring Subprograms You can declare subprograms in any PL/SQL subprogram, block, or package. But, you should declare subprograms at the end of the declarative part after a

Commit statement in pl sql, COMMIT Statement The COMMIT statement expli...

COMMIT Statement The COMMIT statement explicitly makes everlasting changes to the database during the present transaction. The Changes made to the database are not considered e

Closing a cursor - explicit cursor, Closing a Cursor The CLOSE stateme...

Closing a Cursor The CLOSE statements disable the cursor, and the result set becomes undefined. An illustration of the CLOSE statement as shown: CLOSE c1;

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

Parameter and keyword description - select into statement, Parameter and Ke...

Parameter and Keyword Description: select_item: This select_item is a value returned by the SELECT statement, and then assigned to the equivalent variable or field in the

Laws / rules associated with evolution, LAWS / RULES - Dollo's Law ...

LAWS / RULES - Dollo's Law : Living organisms do exhibit evolutionary irreversibility or evolution is irreversible. Williston's Law

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages