Disjunction - sql, PL-SQL Programming

Assignment Help:

Disjunction (OR, ∨)

Again we have nine rows instead of just four and again, when unknown is not involved, the rows are as for 2VL. Also, when anything is paired with true, the result is true, as in 2VL. Our intuition, that "p or q" is true exactly when at least one operand is true, is preserved.

526_Disjunction (OR, ∨).png

Figure: The SQL Truth Table for Disjunction

Now, in the theory book it is noted that disjunction could equally well be defined in terms of conjunction and negation, as

p ∨ q ≡ ¬ (¬ p ∧ ¬ q)

and the truth table in Figure is given as proof of that equivalence. The question arises, does the same equivalence hold in SQL? To answer that we need to look at the revised Figure.

1667_Disjunction 2.png

Figure: SQL Disjunction in Terms of SQL Negation and SQL Conjunction


Related Discussions:- Disjunction - sql

Declaring objects in pl/sql, Declaring Objects: You can use the object ...

Declaring Objects: You can use the object types wherever built-in types like CHAR or NUMBER can be used. In the block below, you can declare object r of type Rational. Then, yo

Parameter and keyword description - sql cursor, Parameter and Keyword Descr...

Parameter and Keyword Description: SQL: This SQL is the name of the implicit SQL cursor. %FOUND: This attribute results TRUE if an INSERT, DELETE, or UPDATE state

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

Disjunction - sql, Disjunction (OR, ∨) Again we have nine rows instead...

Disjunction (OR, ∨) Again we have nine rows instead of just four and again, when unknown is not involved, the rows are as for 2VL. Also, when anything is paired with true, t

Implement a new discount for return shoppers, Brewbean's is implementing a ...

Brewbean's is implementing a new discount for return shoppers - every fifth completed order receives a 10% discount. The count of orders for a shopper is placed in a packaged varia

Overloading method in pl/sql, Overloading: Similar to packaged subprog...

Overloading: Similar to packaged subprograms, methods of the same type can be overloaded. That is, you can use similar name for various methods if their formal parameters diff

Mysql developer/programmer, Project Description: I want somebody who can...

Project Description: I want somebody who can help me with an idea that I have been working on for a few months now. The person will require extensive knowledge of warcraft 3 PvP

Cursors - syntax, Cursors   To execute the multi-row query, the Oracle...

Cursors   To execute the multi-row query, the Oracle opens an unnamed work region which stores the processing information. The cursor names the work region, access the informa

Example of using aggregation on nested tables, Example of Using Aggregation...

Example of Using Aggregation on Nested Tables Example: How many students sat each exam WITH C_ER AS (SELECT CourseId, CAST (TABLE (SELECT DISTINCT StudentId, Mark FROM EXAM

Effects of null for unique specification - sql, Effects of NULL for UNIQUE ...

Effects of NULL for UNIQUE Specification When a UNIQUE specification u for base table t includes a column c that is not subject to a NOT NULL constraint, the appearance of sev

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