diff --git a/NEP2020/2024/BCA/3rdsem/dbms/assignments/normalisation.md b/NEP2020/2024/BCA/3rdsem/dbms/assignments/normalisation.md new file mode 100644 index 0000000..2befe87 --- /dev/null +++ b/NEP2020/2024/BCA/3rdsem/dbms/assignments/normalisation.md @@ -0,0 +1,37 @@ +# Assignment 1 + +## Write a note on decomposition with examples. +Decomposition refers to the division of tables into multiple tables to produce consistency in the data. + +![Types](https://media.geeksforgeeks.org/wp-content/uploads/20240225103808/Screenshot-2024-02-25-103756.png) + +### Types of Decomposition + +There are two types of Decomposition: +- Lossless Decomposition +- Lossy Decomposition + +### Lossless Decomposition +The process in which where we can regain the original relation R with the help of joins from the multiple relations formed after decomposition. This process is termed as lossless decomposition. + +It is used to remove the redundant data from the database while retaining the useful information. + +The lossless decomposition tries to ensure following things: +- While regaining the original relation, no information should be lost. +- If we perform join operation on the sub-divided relations, we must get the original relation. + +EXAMPLE: +There is a relation called R(A,B,C) +|**A**|**B**|**C**| +| ---| ---| ---| +| 55 | 16 | 27 | +| 48 | 52 | 89 | + + + + + +### Lossy decomposition: + +## Source: +- Q1 answer - [GeeksForGeeks](https://www.geeksforgeeks.org/decomposition-in-dbms/) \ No newline at end of file