- If the information is not lost from the relation that is decomposed, then the decomposition will be lossless.
- The result of lossless decomposition after natural joins will be exactly the same relation as it was before the decomposition.
EMPLOYEE Table: The above table is decomposed into two relations: EMPLOYEE and DEPARTMENT
Table 01: EMPLOYEE
Table 02: DEPARTMENT
The Above two tables are joined on the common column “EMP_ID.”
Employee ⋈ Department
The above table is the original table as it was before decomposition. Hence, the decomposition is Lossless join decomposition.