What is lossless join code example

Example 1: lossless join decomposition

In database design, a lossless join decomposition is a decomposition 
of a relation R into relations R1 ,R2 such that a natural join of the 
two smaller relations yields back the original relation. 
This is central in removing redundancy safely from databases while 
preserving the original data.

Example 2: what do we mean by lossless join property in dbms

In database design, a lossless join decomposition is a decomposition of 
a relation into relations. such that a natural join of the two smaller 
relations yields back the original relation. This is central in removing
redundancy safely from databases while preserving the original data.