Close

14/07/2020

What is lossless decomposition with example?

What is lossless decomposition with example?

Lossless Decomposition Decomposition is lossless if it is feasible to reconstruct relation R from decomposed tables using Joins. This is the preferred choice. The information will not lose from the relation when decomposed. The join would result in the same original relation. Let us see an example −

What is decomposition in DBMS with example?

In a database, it breaks the table into multiple tables. If the relation has no proper decomposition, then it may lead to problems like loss of information. Decomposition is used to eliminate some of the problems of bad design like anomalies, inconsistencies, and redundancy.

What is the lossless or non additive join property of decomposition Why is it important?

This property ensures that no spurious tuples are generated when a NATURAL JOIN operation is applied to the relations in the decomposition.

What is lossy and lossless join decomposition?

The decompositions R1, R2, R2… Rn for a relation schema R are said to be Lossless if there natural join results the original relation R. Rn for a relation schema R are said to be Lossy if there natural join results into addition of extraneous tuples with the original relation R.

What do you understand by decomposition in DBMS?

Decomposition in DBMS. Decomposition of a Relation- Definition. : The process of breaking up or dividing a single relation into two or more sub relations is called as decomposition of a relation.

What do you understand by decomposition explain in detail in DBMS?

Decomposition is the process of breaking down in parts or elements. It replaces a relation with a collection of smaller relations. It breaks the table into multiple tables in a database.

What is the difference between lossy and lossless?

Compression can be lossy or lossless . Lossless compression means that as the file size is compressed, the picture quality remains the same – it does not get worse. Also, the file can be decompressed to its original quality. Lossy compression permanently removes data.

How is lossless decomposition used in a DBMS?

Lossless Decomposition in DBMS. Lossless join decomposition is a decomposition of a relation R into relations R1,R2 such that if we perform natural join of two smaller relations it will return the original relation. This is effective in removing redundancy from databases while preserving the original data..

What is the property of Lossless Join Decomposition?

Lossless-join decomposition is a process in which a relation is decomposed into two or more relations. This property guarantees that the extra or less tuple generation problem does not occur and no information is lost from the original relation during the decomposition. It is also known as non-additive join decomposition.

Is the decomposition of a table lossless or lossy?

Decomposition is lossless if it is feasible to reconstruct relation R from decomposed tables using Joins. This is the preferred choice. The information will not lose from the relation when decomposed. The join would result in the same original relation.

Can a relation be both lossless join and dependency preserving?

A relation R is decomposed into two or more only if the decomposition is both lossless join and dependency preserving. Learn more about Other Decompositions here on this page.